Visit our newest sister site!
Hundreds of free aircraft flight manuals
Civilian • Historical • Military • Declassified • FREE!


TUCoPS :: Unix :: General :: csh-man.txt

csh man page




From ringw0rmNOT@gte.net Wed Sep 30 09:58:57 1998
Newsgroups: alt.2600
Subject: Better explanation of csh (long as fuck all)
From: Ringworm <ringw0rmNOT@gte.net>
Date: Wed, 30 Sep 1998 11:58:57 -0500

This is a multi-part message in MIME format.
--------------7232EEEE8CDE47460EDEDF0D
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

-- 
Ringworm
Anti-Archangel #11
http://newbie.darkridge.com
--------------7232EEEE8CDE47460EDEDF0D
Content-Type: text/plain; charset=us-ascii; name="csh.txt"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline; filename="csh.txt"

~ % man csh
 
Reformatting page.  Please wait ... done
 
User Commands                                              csh(1)
 
NAME
     csh - shell command interpreter with a C-like syntax
 
SYNOPSIS
     csh [ -bcefinstvVxX ] [ argument...  ]
 
DESCRIPTION
     csh,  the  C  shell,  is a command interpreter with a syntax
     reminiscent of the C language.  It provides a number of con-
     venient  features for interactive use that are not available
     with the Bourne shell, including filename  completion,  com-
     mand aliasing, history substitution, job control, and a num-
     ber of built-in commands.  As with the Bourne shell,  the  C
     shell  provides variable, command and filename substitution.
 
  Initialization and Termination
     When first started, the C shell normally  performs  commands
     from  the  .cshrc file in your home directory, provided that
     it is readable and you either own it or your real  group  ID
     matches  its  group ID.  If the shell is invoked with a name
     that starts with `-', as when started by login(1), the shell
     runs as a login shell.
 
     If the shell is a login shell, this is the sequence of invo-
     cations: First, commands in /etc/.login    are executed.  Next,
     commands  from  the .cshrc file your       home directory are exe-
     cuted.  Then the shell executes  commands  from  the  .login
     file  in  your home directory; the same permission checks as
     those for .cshrc are       applied to this file.   Typically,  the
     .login  file        contains commands to specify the terminal type
     and environment.  (For an explanation of file  interpreters,
     see below "Command Execution" and exec(2).)
 
     As  a  login shell terminates, it performs commands from the
     .logout file in your home  directory;  the same  permission
     checks as those for .cshrc are applied to this file.
 
  Interactive Operation
     After startup processing is complete, an interactive C shell
     begins reading commands from the  terminal,  prompting  with
     hostname%  (or hostname# for the privileged user).  The shell
     then repeatedly performs the following actions:  a  line  of
     command  input is read and broken into words.       This sequence
     of words is placed on the history list and then  parsed,  as
     described  under  USAGE, below.  Finally, the shell executes
     each command in the current line.
 
  Noninteractive Operation
     When running noninteractively, the shell does not prompt for
     input  from the terminal.  A noninteractive C shell can exe-
     cute a command supplied as an argument on its command  line,
     or interpret commands from a file, also known as a script.
 
SunOS 5.6            Last change: 23 May 1997                   1
 
User Commands                                              csh(1)
 
OPTIONS
     -b  Force  a  "break"  from option processing.  Subse-
               quent command line arguments are  not  interpreted
               as  C  shell  options.  This allows the passing of
               options to a script without confusion.  The  shell
               does  not  run set-user-ID or set-group-ID scripts
               unless this option is present.
 
     -c  Execute the first argument  (which  must  be  pre-
               sent).   Remaining  arguments  are placed in argv,
               the argument-list variable, and passed directly to
               csh.
 
     -e  Exit  if a command terminates abnormally or yields
               a nonzero exit status.
 
     -f  Fast start.  Read neither the .cshrc file, nor the
               .login file (if a login shell) upon startup.
 
     -i  Forced   interactive.   Prompt  for  command  line
               input, even if the standard input does not  appear
               to be a terminal (character-special device).
 
     -n  Parse  (interpret),  but  do not execute commands.
               This option can be used to check C  shell  scripts
               for syntax errors.
 
     -s  Take commands from the standard input.
 
     -t  Read  and  execute  a  single command line.  A `\'
               (backslash) can be used to escape each newline for
               continuation  of  the command line onto subsequent
               input lines.
 
     -v  Verbose.  Set  the  verbose  predefined         variable;
               command input is echoed after history substitution
               (but before other substitutions) and before execu-
               tion.
 
     -V  Set verbose before reading .cshrc.
 
     -x  Echo.   Set the echo variable; echo commands after
               all substitutions and just before execution.
 
     -X  Set echo before reading .cshrc.
 
     Except with the options -c, -i, -s, or -t, the first  nonop-
     tion  argument  is  taken  to  be  the  name of a command or
     script.  It is passed as argument zero, and subsequent argu-
     ments  are  added  to  the argument list for that command or
     script.
 
SunOS 5.6            Last change: 23 May 1997                   2
 
User Commands                                              csh(1)
 
USAGE
  Filename Completion
     When enabled by setting the variable filec, an interactive C
     shell  can complete a partially typed filename or user name.
     When an unambiguous partial filename is followed by  an  ESC
     character on the terminal input line, the shell fills in the
     remaining characters of a matching filename from the working
     directory.
 
     If a partial filename is followed by the EOF character (usu-
     ally typed as CTRL-d), the shell lists  all  filenames  that
     match.  It then prompts once again, supplying the incomplete
     command line typed in so far.
 
     When the last (partial) word begins with a  tilde  (~),  the
     shell  attempts  completion  with a user name, rather than a
     file in the working directory.
 
     The terminal bell signals errors or multiple  matches;  this
     can  be  inhibited  by setting the variable nobeep.        You can
     exclude files with certain suffixes by  listing  those  suf-
     fixes in the variable fignore.  If,        however, the only possi-
     ble completion includes a suffix in  the  list,  it  is  not
     ignored.   fignore does not affect the listing of filenames
     by the EOF character.
 
  Lexical Structure
     The shell splits input lines into words  at  space  and  tab
     characters,  except as noted below.  The characters &, |, ;,
     <, >, (, and )     form separate words;  if  paired,  the  pairs
     form  single  words.  These shell metacharacters can be made
     part of other words, and their special meaning can  be  sup-
     pressed by preceding them with a `\' (backslash).   A newline
     preceded by a \ is equivalent to a space character.
 
     In addition, a string enclosed in matched pairs  of  single-
     quotes  ('),  double-quotes  ("), or backquotes (`), forms a
     partial word; metacharacters in such a string, including any
     space or tab characters, do not form separate words.  Within
     pairs of backquote (`) or   double-quote  (")  characters,  a
     newline  preceded  by a `\' (backslash) gives a true newline
     character.  Additional functions of each type of  quote  are
     described,  below, under Variable Substitution, Command    Sub-
     stitution, and Filename Substitution.
 
     When the shell's input is not a terminal,  the  character  #
     introduces  a comment that continues to the end of the input
     line.  Its special meaning is suppressed when preceded by  a
     \  or enclosed in matching quotes.
 
  Command Line Parsing
 
SunOS 5.6            Last change: 23 May 1997                   3
 
User Commands                                              csh(1)
 
     A  simple  command  is composed of a sequence      of words.  The
     first word (that is not part of an I/O  redirection)  speci-
     fies the command to be executed.  A simple command, or a set
     of simple commands separated by |  or |&   characters, forms  a
     pipeline.  With |, the standard output of  the preceding com-
     mand is redirected to the standard input of the command that
     follows.   With |&, both   the standard error and the standard
     output are redirected through the pipeline.
 
     Pipelines can be separated by semicolons (;), in which  case
     they  are  executed  sequentially.  Pipelines that are sepa-
     rated by && or || form     conditional sequences  in  which  the
     execution of pipelines on the right depends upon the success
     or failure, respectively, of the pipeline on the left.
 
     A pipeline or sequence can be enclosed within parentheses `(
     )'  to  form  a  simple command that can be a component in a
     pipeline or sequence.
 
     A sequence of pipelines can be  executed  asynchronously  or
     "in the background" by appending an `&'; rather than waiting
     for the sequence to finish  before  issuing  a  prompt,  the
     shell  displays  the job number (see Job Control, below)   and
     associated process IDs and prompts immediately.
 
  History Substitution
     History substitution allows you to use words  from  previous
     command lines in the command line you are typing.  This sim-
     plifies spelling corrections and the repetition  of  compli-
     cated commands or arguments.  Command lines are saved in the
     history list, the size of which is controlled by the history
     variable.   The most recent command is retained in any case.
     A history substitution begins with a !   (although  you  can
     change  this with the histchars variable)  and may occur any-
     where on the command  line;  history  substitutions  do  not
     nest.   The !  can be escaped with \ to suppress   its special
     meaning.
 
     Input lines containing history substitutions are  echoed  on
     the terminal after being expanded, but before any other sub-
     stitutions take place or the command gets executed.
 
  Event Designators
     An event designator is a reference to a command  line  entry
     in the history list.
          !     Start a history substitution, except when followed
               by a space character, tab, newline, = or (.
          !!     Refer to the previous command.   By  itself,  this
               substitution repeats the previous command.
          !n     Refer to command line n.
          !-n  Refer    to the current command line minus n.
          !str Refer  to  the  most      recent command starting with
 
SunOS 5.6            Last change: 23 May 1997                   4
 
User Commands                                              csh(1)
 
               str.
          !?str?
               Refer to the most recent command containing str.
          !?str? additional
               Refer to the most recent  command  containing  str
               and  append additional   to that referenced command.
          !{command} additional
               Refer to the most recent  command  beginning  with
               command  and  append additional  to that referenced
               command.
          ^previous_word^replacement^
               Repeat the previous  command  line  replacing  the
               string  previous_word with the string replacement.
               This is equivalent to the history substitution:
                       !:s/previous_word/replacement/.
 
               To re-execute a specific previous command AND make
               such a substitution, say, re-executing command #6,
                       !:6s/previous_word/replacement/.
 
  Word Designators
     A `:' (colon) separates the  event  specification   from  the
     word  designator.   It can be omitted if the word designator
     begins with a ^, $, *, -  or  %.   If       the  word  is  to  be
     selected  from the previous command, the second !   character
     can be omitted from the event specification.  For  instance,
     !!:1  and  !:1  both refer to the first word of the        previous
     command, while !!$ and !$ both refer to the last word      in the
     previous command.  Word designators include:
 
          #     The entire command line typed so far.
          0     The first input word (command).
          n     The n'th argument.
          ^     The first argument, that is, 1.
          $     The last argument.
          %     The word matched by (the most recent) ?s search.
          x-y  A range of words; -y abbreviates 0-y.
          *     All  the  arguments,  or  a null value if there is
               just one word in the event.
          x*     Abbreviates x-$.
          x-     Like x* but omitting   word $.
 
  Modifiers
     After the optional word designator, you can add one  of  the
     following modifiers, preceded by a :.
 
          h     Remove  a trailing pathname component, leaving the
               head.
          r     Remove a trailing suffix of the form `.xxx', leav-
               ing the basename.
          e     Remove  all but the suffix, leaving the Extension.
          s/l/r/
 
SunOS 5.6            Last change: 23 May 1997                   5
 
User Commands                                              csh(1)
 
               Substitute r for l.
          t     Remove all leading  pathname  components,  leaving
               the tail.
          &     Repeat the previous substitution.
          g     Apply  the  change  to  the  first occurrence of a
               match in each word, by prefixing  the  above  (for
               example, g&).
          p     Print the new command but do not execute it.
          q     Quote the substituted words, escaping further sub-
               stitutions.
          x     Like q, but break into  words at each space charac-
               ter, tab or newline.
 
     Unless  preceded by a g, the modification  is applied only to
     the first string that matches l;   an  error  results  if  no
     string matches.
 
     The  left-hand side of substitutions are not regular expres-
     sions, but character strings.  Any character can be used  as
     the  delimiter in place of /.  A backslash quotes  the delim-
     iter character.  The character &,  in the right hand side, is
     replaced  by the text from the left-hand-side.  The & can  be
     quoted with a backslash.  A null l uses the previous  string
     either from a l or from a  contextual scan string s from !?s.
     You can omit the rightmost delimiter if  a  newline  immedi-
     ately follows r; the rightmost ?    in a context scan can sim-
     ilarly be omitted.
 
     Without an event specification, a history  reference  refers
     either  to  the  previous  command, or to a previous history
     reference on the command line (if any).
 
  Quick Substitution
     ^l^r^
          This  is  equivalent  to  the   history   substitution:
          !:s/l/r/.
 
  Aliases
     The C shell maintains a list of aliases that you can create,
     display, and modify using the alias  and  unalias  commands.
     The shell checks the first word in each command to see if it
     matches the name of an existing alias.  If it does, the com-
     mand  is reprocessed with the alias definition replacing its
     name; the history substitution mechanism is  made  available
     as  though  that command were the previous input line.  This
     allows history substitutions, escaped with  a  backslash  in
     the  definition,  to  be  replaced  with actual command line
     arguments when the alias is used.  If no  history  substitu-
     tion is called for, the arguments remain unchanged.
 
     Aliases  can  be  nested.   That is, an alias definition can
     contain the name  of  another  alias.   Nested  aliases  are
 
SunOS 5.6            Last change: 23 May 1997                   6
 
User Commands                                              csh(1)
 
     expanded  before any history substitutions is applied.  This
     is useful in pipelines such as
 
          alias  lm 'ls  -l      \!*     |  more'
 
     which  when  called,  pipes  the  output  of  ls(1)  through
     more(1).
 
     Except  for  the  first  word, the name of the alias may not
     appear in its definition, nor in any alias  referred  to  by
     its definition.  Such loops are detected, and cause an error
     message.
 
  I/O Redirection
     The following metacharacters indicate  that  the  subsequent
     word  is  the name of a file to which the command's standard
     input, standard output, or  standard  error  is  redirected;
     this  word is variable, command, and filename expanded sepa-
     rately from the rest of the command.
 
     <               Redirect the standard input.
 
     <<word       Read the standard input, up to a line that is
                    identical  with word, and place     the resulting
                    lines in a temporary file.   Unless  word  is
                    escaped  or quoted, variable and command sub-
                    stitutions  are  performed  on  these  lines.
                    Then, the pipeline is invoked with the tempo-
                    rary file as its standard input.  word is not
                    subjected  to  variable, filename, or command
                    substitution, and each line is compared to it
                    before any substitutions are performed by the
                    shell.
 
     >    >!     >&     >&!
                    Redirect the standard output to a  file.   If
                    the  file  does not exist, it is created.  If
                    it does exist, it is overwritten; its  previ-
                    ous contents are lost.
 
                    When  set,  the  variable  noclobber prevents
                    destruction of existing files.  It also  pre-
                    vents redirection to terminals and /dev/null,
                    unless one of the !  forms  is  used.   The  &
                    forms  redirect  both standard output and the
                    standard error  (diagnostic  output)  to  the
                    file.
 
     >>   >>&   >>!   >>&!
                    Append  the  standard  output.   Like  >, but
                    places output at the end of the  file  rather
                    than overwriting it.  If noclobber  is set, it
 
SunOS 5.6            Last change: 23 May 1997                   7
 
User Commands                                              csh(1)
 
                    is an error for the file not to exist, unless
                    one  of  the  !   forms is  used.  The & forms
                    append both the standard error  and  standard
                    output to the file.
 
  Variable Substitution
     The  C  shell maintains a set of variables, each of which  is
     composed of a name and     a value.  A variable name consists      of
     up  to  20 letters and digits, and starts with a letter (the
     underscore is considered a letter).  A variable's value is a
     space-separated list of zero or more words.
 
     To refer to a variable's value, precede its name with a `$'.
     Certain references (described below) can be used  to  select
     specific  words from the value, or to display other informa-
     tion about the variable.  Braces can be used to insulate the
     reference from other characters in an input-line word.
 
     Variable  substitution  takes  place after the input line is
     analyzed, aliases are resolved,  and  I/O  redirections  are
     applied.   Exceptions to this are variable references in I/O
     redirections (substituted at the  time  the  redirection  is
     made), and backquoted strings (see Command Substitution).
 
     Variable  substitution  can be suppressed by preceding the $
     with a  \,  except  within  double-quotes   where  it  always
     occurs.   Variable substitution is suppressed inside of sin-
     gle-quotes.  A $ is escaped if followed by a  space  charac-
     ter, tab or newline.
 
     Variables  can be created, displayed, or destroyed using the
     set and    unset commands.  Some variables  are  maintained  or
     used by the shell.  For instance, the argv variable contains
     an image of the shell's argument  list.   Of  the  variables
     used  by the shell, a number are toggles; the shell does not
     care what their value is, only whether they are set or  not.
 
     Numerical  values can be operated on as numbers (as with the
     @  built-in command).   With  numeric  operations,  an  empty
     value  is  considered  to be zero; the second and subsequent
     words of multiword values are ignored.  For  instance,  when
     the verbose        variable is set to any value (including an empty
     value), command input is echoed on the terminal.
 
     Command and filename substitution is subsequently applied to
     the words that result from the variable substitution, except
     when suppressed by double-quotes, when noglob is  set  (sup-
     pressing  filename  substitution),  or when the reference is
     quoted with the :q modifier.  Within double-quotes, a refer-
     ence  is  expanded  to  form (a portion of) a quoted string;
     multiword values are expanded  to  a  string  with  embedded
     space  characters.   When  the :q modifier is applied to   the
 
SunOS 5.6            Last change: 23 May 1997                   8
 
User Commands                                              csh(1)
 
     reference, it is  expanded  to  a  list  of  space-separated
     words, each of which is quoted to prevent subsequent command
     or filename substitutions.
 
     Except as noted below, it is an error to refer to a variable
     that is not set.
 
     $var
     ${var}       These are replaced by words from the value of
                    var, each separated by a    space character.  If
                    var  is an environment variable,    its value is
                    returned (but `:'   modifiers  and  the  other
                    forms given below are not available).
 
     $var[index]
     ${var[index]}       These  select  only  the indicated words from
                    the value of var.  Variable  substitution  is
                    applied  to  index,  which may      consist of (or
                    result in) a either single number,  two  num-
                    bers  separated  by  a  `-',  or an asterisk.
                    Words are indexed  starting  from  1;  a  `*'
                    selects  all words.  If the first number of a
                    range is  omitted  (as  with  $argv[-2]),   it
                    defaults to 1.  If the last number of a range
                    is omitted (as with $argv[1-]),  it  defaults
                    to  $#var  (the  word       count).   It is not an
                    error for a range to be empty if  the  second
                    argument is omitted (or within range).
 
     $#name
     ${#name}       These  give  the number of words in the vari-
                    able.
 
     $0       This substitutes the name of  the  file  from
                    which  command input is being read except for
                    setuid shell scripts.  An error occurs if the
                    name is not known.
 
     $n
     ${n}               Equivalent to $argv[n].
 
     $*       Equivalent to $argv[*].
 
     The modifiers :e, :h, :q, :r, :t, and :x can be applied (see
     History Substitution), as can :gh,  :gt,   and  :gr.   If  {}
     (braces) are used, then the modifiers must appear within the
     braces.  The current implementation  allows  only  one  such
     modifier per expansion.
 
     The  following  references  may not be modified with : modi-
     fiers.
 
SunOS 5.6            Last change: 23 May 1997                   9
 
User Commands                                              csh(1)
 
     $?var
     ${?var}
          Substitutes the string 1 if var is    set or 0  if  it  is
          not set.
 
     $?0  Substitutes 1 if the current input    filename is known or
          0 if it is not.
 
     $$   Substitute the process number of the (parent) shell.
 
     $<   Substitutes   a line from the  standard  input,  with  no
          further  interpretation  thereafter.  It can be used to
          read from the keyboard in a C shell script.
 
  Command and   Filename Substitutions
     Command and filename substitutions are  applied  selectively
     to  the arguments of built-in commands.  Portions of expres-
     sions that are not evaluated are  not  expanded.   For  non-
     built-in commands, filename expansion of the command name is
     done separately from that of the  argument  list;  expansion
     occurs in a subshell, after I/O redirection is performed.
 
  Command Substitution
     A  command  enclosed by backquotes (`...`) is performed by a
     subshell.  Its standard output is broken into separate words
     at  each  space  character,  tab and newline; null words are
     discarded.  This text replaces the backquoted string on  the
     current  command  line.   Within double-quotes, only newline
     characters force new words; space  and  tab  characters  are
     preserved.   However,  a  final  newline  is ignored.  It is
     therefore possible for a command  substitution  to  yield  a
     partial word.
 
  Filename Substitution
     Unquoted  words  containing any of the characters *, ?, [ or
     {, or that  begin   with  ~,  are   expanded  (also  known  as
     globbing)  to an alphabetically sorted list of filenames, as
     follows:
 
     *               Match any (zero or more) characters.
 
     ?               Match any single character.
 
     [  ... ]         Match any single character  in  the  enclosed
                    list(s)  or  range(s).  A list is a string of
                    characters.  A range is two characters  sepa-
                    rated  by  a  dash  (-), and includes all the
                    characters in between in the ASCII  collating
                    sequence (see ascii(5)).
 
     {  str, str, ...  }
                    Expand  to  each string (or filename-matching
 
SunOS 5.6            Last change: 23 May 1997                  10
 
User Commands                                              csh(1)
 
                    pattern) in the comma-separated list.  Unlike
                    the  pattern-matching  expressions above, the
                    expansion of this construct  is  not  sorted.
                    For  instance, {b,a} expands to `b' `a', (not
                    `a' `b').    As special cases, the characters {
                    and  },  along with the string {}, are passed
                    undisturbed.
 
     ~[user]     Your home  directory,  as  indicated  by  the
                    value  of the variable home, or     that of user,
                    as indicated by the password entry for  user.
 
     Only  the  patterns *, ?    and [...]  imply pattern matching;
     an error results if no filename matches a pattern that  con-
     tains  them.  The `.'  (dot character), when it is the first
     character in a  filename  or  pathname  component,  must  be
     matched  explicitly.   The  /  (slash)  must also  be matched
     explicitly.
 
  Expressions and       Operators
     A number of C shell built-in commands accept expressions, in
     which  the  operators are similar to those of C and have the
     same precedence.  These expressions typically appear in  the
     @,  exit,  if, set and while commands, and are often used to
     regulate the flow of control for executing commands.  Compo-
     nents of an expression are separated by white space.
 
     Null  or missing values are considered 0.  The result of all
     expressions is a string, which may  represent  decimal  num-
     bers.
 
     The  following  C  shell  operators  are grouped in order of
     precedence:
 
          (...)         grouping
          ~                    one's complement
          !                    logical negation
          *   /   %              multiplication, division, remainder
                              (These are right associative, which
                              can  lead  to  unexpected  results.
                              Group  combinations explicitly with
                              parentheses.)
          +   -         addition, subtraction  (also  right
                              associative)
          <<     >>               bitwise  shift  left, bitwise shift
                              right
          <   >   <=   >=           less than, greater than, less  than
                              or  equal to, greater than or equal
                              to
          ==     !=     =~   !~   equal to,     not equal  to,  filename-
                              substitution      pattern     match
                              (described    below),     filename-
 
SunOS 5.6            Last change: 23 May 1997                  11
 
User Commands                                              csh(1)
 
                              substitution pattern mismatch
          &                    bitwise AND
          ^                    bitwise XOR (exclusive or)
          |                    bitwise inclusive OR
          &&                    logical AND
          ||                    logical OR
 
     The operators: ==, !=,     =~, and !~ compare their arguments as
     strings; other operators use numbers.  The operators =~    and
     !~  each   check whether or not a string to the left matches a
     filename substitution pattern on the  right.   This  reduces
     the need for switch statements when pattern-matching       between
     strings is all that is required.
 
     Also available are file inquiries:
          -r filename    Return true, or 1 if  the  user  has  read
                       access.  Otherwise it returns false, or 0.
          -w filename    True if the user has write access.
          -x filename    True if the user  has  execute  permission
                       (or search permission on a directory).
          -e filename    True if filename exists.
          -o filename    True if the user owns filename.
          -z filename    True   if   filename  is  of  zero  length
                       (empty).
          -f filename    True if filename is a plain file.
          -d filename    True if filename is a directory.
 
     If filename does not exist  or  is  inaccessible,  then  all
     inquiries return false.
 
     An inquiry as to the success of a command is also available:
 
          { command }   If command runs successfully, the  expres-
                       sion  evaluates to true, 1.  Otherwise, it
                       evaluates  to  false,  0.   (Note:    Con-
                       versely,  command        itself typically returns
                       0 when it runs successfully, or some other
                       value  if it encounters a problem.  If you
                       want to get at the  status  directly,  use
                       the  value  of  the status       variable rather
                       than this expression).
 
  Control Flow
     The shell contains a number of commands to regulate the flow
     of  control in scripts and within limits, from the terminal.
     These commands operate by forcing the shell either to reread
     input  (to  loop), or to skip input under certain conditions
     (to branch).
 
     Each occurrence of a foreach, switch,      while,  if...then  and
     else  built-in      command must appear as the first word on its
     own input line.
 
SunOS 5.6            Last change: 23 May 1997                  12
 
User Commands                                              csh(1)
 
     If the shell's input is not seekable and  a  loop  is  being
     read,  that  input  is  buffered.   The shell performs seeks
     within the  internal  buffer  to  accomplish  the  rereading
     implied by the loop.  (To the extent that this allows, back-
     ward goto commands will succeed on nonseekable     inputs.)
 
  Command Execution
     If the command is a C shell built-in command, the shell exe-
     cutes it directly.  Otherwise, the shell searches for a file
     by that name with execute access.  If the command name  con-
     tains  a  /,  the  shell takes it as a pathname, and searches
     for it.  If the command name does not contain a /, the shell
     attempts  to resolve it to a pathname, searching each direc-
     tory in the path variable for the  command.   To  speed  the
     search, the shell uses its hash table (see the rehash built-
     in command) to eliminate directories that have no applicable
     files.   This  hashing  can  be  disabled with the -c or   -t,
     options, or the unhash built-in command.
 
     As a special case, if there is no  /  in   the  name  of  the
     script  and there is an alias for the word shell, the      expan-
     sion of the shell alias is prepended (without       modification)
     to  the  command  line.   The system attempts to execute the
     first word of this  special  (late-occurring)  alias,  which
     should  be  a full pathname.  Remaining words of the alias's
     definition, along with the  text  of  the  input  line,  are
     treated as arguments.
 
     When  a  pathname  is  found that has proper execute permis-
     sions, the shell forks a new process and  passes  it,  along
     with  its arguments, to the kernel using the execve() system
     call (see exec(2)).  The kernel then attempts to overlay the
     new  process  with  the  desired program.  If the file is an
     executable binary (in a.out(4) format) the  kernel  succeeds
     and begins executing the new process.  If the file is a text
     file and the first line begins with #!,    the  next  word  is
     taken  to  be the pathname of a shell (or command) to inter-
     pret that script.  Subsequent words on the  first  line  are
     taken  as options for that shell.  The kernel invokes (over-
     lays) the indicated shell, using the name of the  script  as
     an argument.
 
     If  neither of the above conditions holds, the kernel cannot
     overlay the file and the execve() call fails       (see  exec(2));
     the  C shell then attempts to execute the file by spawning a
     new shell, as follows:
 
          o If  the first character of the file is a #, a C  shell
          is invoked.
          o Otherwise,  a Bourne shell is invoked.
 
SunOS 5.6            Last change: 23 May 1997                  13
 
User Commands                                              csh(1)
 
  Signal Handling
     The  shell  normally  ignores QUIT signals.  Background jobs
     are immune to signals generated from the keyboard, including
     hangups  (HUP).   Other  signals  have the values that the C
     shell inherited from its environment.  The shell's  handling
     of  interrupt  and  terminate  signals within scripts can be
     controlled by the onintr  built-in  command.         Login  shells
     catch  the  TERM signal; otherwise, this signal is passed on
     to child processes.  In no case are interrupts allowed  when
     a login shell is reading the .logout file.
 
  Job Control
     The  shell  associates  a  numbered  job  with     each command
     sequence to keep track of those commands that are running in
     the background or have been stopped with TSTP signals (typi-
     cally CTRL-z).  When a command or  command  sequence  (semi-
     colon separated list) is started in the background using the
     &  metacharacter, the shell displays a line with the job num-
     ber in brackets and a list of associated process numbers:
 
          [1] 1234
 
     To  see the current list of jobs, use the jobs     built-in com-
     mand.  The job most recently stopped (or put into the  back-
     ground  if  none  are stopped) is referred to as the current
     job and is indicated with a `+'.   The previous job is  indi-
     cated  with  a  `-';  when  the current job is terminated  or
     moved to the foreground, this job takes its  place  (becomes
     the new current job).
 
     To  manipulate  jobs, refer to the bg, fg, kill, stop,     and %
     built-in commands.
 
     A reference to a job begins with a `%'.  By itself, the per-
     cent-sign refers to the current job.
 
     %    %+     %%      The current job.
     %-       The previous job.
     %j       Refer to job j as in: `kill -9 %j'.  j can be
                    a job number, or a string that uniquely spec-
                    ifies  the  command  line  by  which  it  was
                    started; `fg %vi' might bring       a  stopped  vi
                    job to the foreground, for instance.
     %?string       Specify  the  job  for which the command line
                    uniquely contains string.
 
     A job running in the background stops when  it  attempts  to
     read  from  the terminal.  Background jobs can normally pro-
     duce output, but this can  be  suppressed  using  the  `stty
     tostop' command.
 
SunOS 5.6            Last change: 23 May 1997                  14
 
User Commands                                              csh(1)
 
  Status Reporting
     While  running interactively, the shell tracks the status of
     each job and reports whenever the job  finishes  or  becomes
     blocked.   It  normally displays a message to this effect as
     it issues a prompt, in order to avoid disturbing the appear-
     ance of your input.  When set, the notify variable indicates
     that the shell is to report status changes immediately.   By
     default, the notify command marks the current process; after
     starting a background job, type notify to mark it.
 
  Built-In Commands
     Built-in commands are executed within the  C  shell.   If  a
     built-in  command  occurs  as  any  component  of a pipeline
     except the last, it is executed in a subshell.
 
     :          Null command.  This command  is  interpreted,  but
               performs no action.
 
     alias      [ name [ def ] ]
               Assign  def  to  the alias name. def is a list of
               words that may contain  escaped  history-substitu-
               tion  metasyntax.  name is not allowed to be     alias
               or unalias.  If def is   omitted, the current  defi-
               nition  for  the alias name is displayed.  If both
               name     and def are omitted,     all  aliases  are  dis-
               played with their definitions.
 
     bg [ %job ... ]
               Run  the  current  or  specified jobs in the back-
               ground.
 
     break          Resume execution after  the  end     of  the  nearest
               enclosing  foreach  or  while loop.      The remaining
               commands on the current line are  executed.   This
               allows  multilevel  breaks to be written as a list
               of break commands, all on one line.
 
     breaksw   Break from a switch, resuming after      the endsw.
 
     case label:
               A label in a switch statement.
 
     cd [ dir ]
     chdir      [ dir ]
               Change the shell's working directory to  directory
               dir.      If no argument is given, change to the home
               directory of the user.  If dir is a relative path-
               name not found in the current directory, check for
               it in those directories listed in the cdpath vari-
               able.   If  dir  is  the  name of a shell variable
               whose value starts with a /, change to the  direc-
               tory named by that value.
 
SunOS 5.6            Last change: 23 May 1997                  15
 
User Commands                                              csh(1)
 
     continue  Continue  execution  of  the next iteration of the
               nearest enclosing while or foreach loop.
 
     default:  Labels the default case  in  a  switch  statement.
               The  default  should  come  after all case labels.
               Any remaining commands on  the  command  line  are
               first executed.
 
     dirs [     -l ]
               Print  the  directory  stack,  most  recent to the
               left; the first directory  shown  is  the  current
               directory.  With the -l argument, produce an unab-
               breviated printout; use of the ~ notation is  sup-
               pressed.
 
     echo [     -n ] list
               The words in list are written to the     shell's stan-
               dard output, separated by space  characters.   The
               output  is terminated with a newline unless the -n
               option is used.
               csh will, by default,    invoke its built-in echo, if
               echo     is called without the full pathname of a Unix
               command, regardless of the configuration  of  your
               PATH     (see echo(1)).
 
     eval argument...
               Reads the arguments as input to the shell and exe-
               cutes the resulting command(s).  This  is  usually
               used  to  execute commands generated as the result
               of command or variable substitution.  See tset(1B)
               for an example of how to use eval.
 
     exec command
               Execute  command in  place  of the current shell,
               which terminates.
 
     exit [     (expr) ]
               The calling shell or shell  script  exits,  either
               with  the value of the status variable or with the
               value specified by the expression expr.
 
     fg [ %job ]
               Bring the current or specified job into the  fore-
               ground.
 
     foreach var (wordlist)
        ...
     end          The  variable var is successively set to each mem-
               ber of wordlist.  The sequence of commands between
               this  command and the matching end is    executed for
               each new value of var.  Both foreach and end  must
               appear alone on separate lines.
 
SunOS 5.6            Last change: 23 May 1997                  16
 
User Commands                                              csh(1)
 
               The  built-in command continue may be used to ter-
               minate the execution of the current  iteration  of
               the  loop  and  the  built-in command break      may be
               used to terminate execution of  the  foreach  com-
               mand.   When  this command is read from the termi-
               nal, the  loop  is  read  once  prompting  with  ?
               before any statements in the loop are executed.
 
     glob wordlist
               Perform  filename  expansion  on  wordlist.   Like
               echo, but no     \ escapes are recognized.  Words  are
               delimited by NULL characters     in the output.
 
     goto label
               The  specified  label  is a      filename and a command
               expanded to yield a label.  The shell rewinds  its
               input  as much as possible and searches for a line
               of the form label:       possibly preceded by  space  or
               tab  characters.   Execution  continues  after the
               indicated line.  It is an error to jump to a label
               that  occurs  between a while or for built-in com-
               mand and its corresponding end.
 
     hashstat  Print a statistics line indicating  how  effective
               the  internal hash table for the path variable has
               been at locating commands  (and  avoiding  execs).
               An  exec  is      attempted  for each component of the
               path     where the hash function indicates a  possible
               hit and in each component that does not begin with
               a `/'.   These statistics only reflect  the  effec-
               tiveness  of  the  path  variable,  not the cdpath
               variable.
 
     history [ -hr ] [ n ]
               Display the history list; if n is  given,  display
               only the n most  recent events.
 
               -r   Reverse  the  order  of  printout    to be most
                    recent first rather than oldest first.
 
               -h   Display the history list without leading num-
                    bers.  This is used to produce files suitable
                    for sourcing using the -h   option to source.
 
     if (expr) command
               If the specified expression evaluates to true, the
               single  command with arguments is        executed.  Vari-
               able substitution on command happens early, at the
               same  time it does for the rest of the if command.
               command must be a        simple command, not a  pipeline,
               a  command  list, or a parenthesized command list.
               Note:  I/O redirection  occurs  even  if  expr  is
 
SunOS 5.6            Last change: 23 May 1997                  17
 
User Commands                                              csh(1)
 
               false,  when  command  is         not    executed (this is a
               bug).
 
     if (expr) then
     ...
     else if (expr2) then
     ...
     else
     ...
     endif          If expr     is true, commands up to the first else are
               executed.   Otherwise,  if expr2 is      true, the com-
               mands between the else if and the second else    are
               executed.   Otherwise,  commands  between the else
               and the endif are executed.       Any number of else     if
               pairs  are  allowed,  but only one else.  Only one
               endif is needed, but it is       required.   The  words
               else      and endif      must be the first nonwhite charac-
               ters on a line.  The if must appear alone  on    its
               input line or after an else.
 
     jobs[-l]  List the active jobs under       job control.
 
               -l   List  process  IDs, in addition to the normal
                    information.
 
     kill [     -sig ] [ pid ] [        %job ] ...
     kill -l   Send the TERM (terminate) signal, by  default,    or
               the signal specified, to the specified process ID,
               the job indicated, or    the  current  job.      Signals
               are  either  given by number or by name.  There is
               no default.  Typing kill does not send a signal to
               the current job.  If the signal being sent is TERM
               (terminate) or HUP (hangup), then the    job or  pro-
               cess is sent a CONT (continue) signal as well.
 
               -l   List the signal names that can be   sent.
 
     limit      [ -h ] [ resource [ max-use ] ]
               Limit  the  consumption  by the current process or
               any process it spawns, each not to exceed  max-use
               on the specified resource.  If max-use is        omitted,
               print the current limit; if resource  is  omitted,
               display  all  limits.  (Run the sysdef(1M)       command
               to obtain the maximum  possible  limits  for  your
               system.   The  values reported are in hexadecimal,
               but can be translated into decimal  numbers  using
               the bc(1) command).
 
               -h   Use  hard    limits instead of the current lim-
                    its.  Hard limits impose  a  ceiling  on  the
                    values of the current limits.  Only the priv-
                    ileged user may raise the hard limits.
 
SunOS 5.6            Last change: 23 May 1997                  18
 
User Commands                                              csh(1)
 
               resource is one of:
 
                    cputime       Maximum CPU seconds  per  pro-
                                   cess.
                    filesize       Largest  single  file allowed;
                                   limited to  the  size  of  the
                                   filesystem.  (see df(1M)).
                    datasize (heapsize)
                                   Maximum  data  size (including
                                   stack) for the process.   This
                                   is  the  size  of your virtual
                                   memory See swap(1M).
                    stacksize       Maximum  stack  size  for  the
                                   process.  See swap(1M).
                    coredumpsize   Maximum      size  of  a core dump
                                   (file).  This limited  to  the
                                   size of the filesystem.
                    descriptors    Maximum       number    of   file
                                   descriptors.  Run sysdef().
                    memorysize     Maximum size of  virtual  mem-
                                   ory.
 
               max-use is a number, with        an optional scaling fac-
               tor, as follows:
 
                    nh   Hours (for cputime).
                    nk   n kilobytes.   This is the  default
                               for all but cputime.
                    nm   n   megabytes    or   minutes  (for
                               cputime).
                    mm:ss           Minutes and seconds (for cputime).
 
               Example  of  limit:   to  limit the size of a core
               file dump to 0 Megabytes, type the following:
                    limit coredumpsize  0M
 
     login      [ username| -p ]
               Terminate a login shell and invoke login(1).   The
               .logout  file  is         not  processed.  If username is
               omitted, login prompts for the name      of a user.
 
               -p   Preserve the current environment (variables).
 
     logout    Terminate a login shell.
 
     nice [     +n | -n ] [     command ]
               Increment the process priority value for the shell
               or for command by         n.   The  higher  the   priority
               value,  the  lower  the priority of a process, and
               the slower it runs.  When given, command is always
               run  in a subshell, and the restrictions placed on
               commands in simple if commands   apply.  If  command
 
SunOS 5.6            Last change: 23 May 1997                  19
 
User Commands                                              csh(1)
 
               is omitted, nice increments the value for the cur-
               rent shell.  If no increment  is  specified,  nice
               sets  the  process priority value to 4.  The range
               of process priority values  is  from  -20  to  20.
               Values  of  n  outside this range set the value  to
               the lower, or  to  the  higher  boundary,  respec-
               tively.
 
               +n   Increment   the process priority value by n.
 
               -n   Decrement    by  n.   This  argument can be used
                    only by the privileged user.
 
     nohup      [ command ]
               Run command with HUPs ignored.  With no arguments,
               ignore  HUPs throughout the remainder of a script.
               When given, command is always run        in  a  subshell,
               and  the restrictions placed on commands in simple
               if statements apply.  All processes detached  with
               & are effectively nohup'd.
 
     notify [ %job ] ...
               Notify  the user asynchronously when the status of
               the current job or specified jobs changes.
 
     onintr [ -|        label]
               Control the action of  the  shell  on  interrupts.
               With  no  arguments,  onintr  restores the       default
               action of the shell  on  interrupts.   (The  shell
               terminates shell scripts and returns to the termi-
               nal command input level).  With  the  -   argument,
               the  shell  ignores  all interrupts.  With a label
               argument, the shell executes a goto label when   an
               interrupt  is  received  or a child process termi-
               nates because it was interrupted.
 
     popd [     +n ] Pop the directory stack and cd     to  the  new  top
               directory.   The  elements  of the directory stack
               are numbered from 0 starting at the top.
 
               +n   Discard the n'th    entry in the stack.
 
     pushd      [ +n | dir]
               Push a directory onto the directory  stack.   With
               no arguments, exchange the top two elements.
 
               +n   Rotate the n'th entry to    the top of the stack
                    and cd to   it.
 
               dir  Push the    current working directory  onto  the
                    stack and change to dir.
 
SunOS 5.6            Last change: 23 May 1997                  20
 
User Commands                                              csh(1)
 
     rehash    Recompute        the internal hash table of the contents
               of directories listed  in  the  path      variable  to
               account  for  new  commands  added.  Recompute the
               internal hash table of the contents of directories
               listed  in  the cdpath variable to       account for new
               directories added.
 
     repeat count command
               Repeat command count     times.  command is subject to
               the  same  restrictions  as  with  the one-line if
               statement.
 
     set [var [ = value ] ]
     set var[n] = word
               With no arguments, set displays the values of     all
               shell  variables.   Multiword values are displayed
               as a parenthesized list.  With  the  var  argument
               alone,  set  assigns     an empty (null) value to the
               variable var.     With arguments of the  form  var  =
               value set assigns value to var, where value      is one
               of:
 
                    word            A single word (or quoted string).
                    (wordlist)  A  space-separated  list of words
                                enclosed in parentheses.
 
               Values are command and  filename  expanded  before
               being  assigned.   The  form  set  var[n]  =  word
               replaces the n'th word in a multiword  value  with
               word.
 
     setenv [ VAR [ word ]      ]
               With no arguments, setenv displays       all environment
               variables.  With the VAR argument, setenv sets the
               environment  variable  VAR to    have an empty (null)
               value.  (By convention, environment variables  are
               normally  given  upper-case names.)  With both VAR
               and word arguments, setenv  sets  the    environment
               variable  NAME  to  the  value word, which must be
               either a single word or a quoted string.  The most
               commonly  used  environment variables, USER,     TERM,
               and  PATH,  are  automatically  imported  to       and
               exported  from  the  csh variables user, term, and
               path; there is no need to use  setenv    for  these.
               In  addition,  the  shell sets the PWD environment
               variable from the csh    variable  cwd  whenever  the
               latter changes.
 
               The  environment  variables LC_CTYPE, LC_MESSAGES,
               LC_TIME, LC_COLLATE, LC_NUMERIC,  and  LC_MONETARY
               take  immediate  effect  when changed within the C
               shell.
 
SunOS 5.6            Last change: 23 May 1997                  21
 
User Commands                                              csh(1)
 
                    If any of  the  LC_*  variables      (  LC_CTYPE,
                    LC_MESSAGES, LC_TIME, LC_COLLATE, LC_NUMERIC,
                    and LC_MONETARY ) (see  environ(5))  are    not
                    set   in  the  environment,  the  operational
                    behavior of csh for each    corresponding locale
                    category  is  determined  by the value of the
                    LANG environment variable.  If LC_ALL is set,
                    its  contents  are  used to override both the
                    LANG and the other LC_* variables.   If  none
                    of the above variables is set in the environ-
                    ment, the "C"  (U.S. style) locale determines
                    how csh behaves.
 
                    LC_CTYPE
                         Determines  how  csh handles characters.
                         When LC_CTYPE is set to a  valid  value,
                         csh     can  display  and  handle  text and
                         filenames  containing  valid  characters
                         for that locale.
 
                    LC_MESSAGES
                         Determines  how  diagnostic and informa-
                         tive  messages   are   presented.   This
                         includes  the  language and style of the
                         messages and the correct form of  affir-
                         mative  and  negative responses.  In the
                         "C" locale, the messages  are  presented
                         in the default form found in the program
                         itself (in most cases, U.S./English).
 
                    LC_NUMERIC
                         Determines the value of the radix  char-
                         acter  (decimal  point  (".") in the "C"
                         locale) and  thousand  separator  (empty
                         string ("") in the "C" locale).
 
     shift      [ variable ]
               The  components of argv, or variable, if supplied,
               are shifted to the left, discarding the first com-
               ponent.  It is an error for the variable not to be
               set or to have a null value.
 
     source [ -h ] name
               Reads commands from name.  source commands may    be
               nested,  but  if  they  are  nested too deeply the
               shell may run out of file descriptors.   An  error
               in  a  sourced  file  at  any level terminates all
               nested source commands.
 
               -h        Place commands from the file name      on  the
                       history list without executing them.
 
SunOS 5.6            Last change: 23 May 1997                  22
 
User Commands                                              csh(1)
 
     stop %jobid ...
               Stop the current or specified background job.
 
     stop pid ...
               Stop the specified process, pid.  (see ps(1)).
 
     suspend   Stop  the         shell  in its tracks, much as if it had
               been sent a stop signal with  ^Z.   This  is  most
               often used to stop shells started by su.
 
     switch (string)
     case label:
     ...
     breaksw
     ...
     default:
     ...
     breaksw
     endsw
               Each  label       is  successively matched, against the
               specified string, which is       first command and file-
               name  expanded.  The file metacharacters *, ?    and
               [...]    may be used in the case labels,  which  are
               variable  expanded.   If  none of the labels match
               before  a  "default"  label  is  found,  execution
               begins  after the default label.  Each case state-
               ment and the default statement must appear at  the
               beginning  of a line.  The command breaksw contin-
               ues execution after the endsw.  Otherwise  control
               falls  through  subsequent case and default state-
               ments as with C.  If no label matches and there is
               no default, execution continues after the endsw.
 
     time [     command ]
               With  no argument, print a summary of time used by
               this C shell and its children.  With  an  optional
                command, execute  command         and print a summary of
               the time it uses.
 
               As of this writing, the time     built-in command does
               NOT compute the last 6 fields of output, rendering
               the output to erroneously report the value "0" for
               these fields.
 
                       example %time ls -R
                       9.0u     11.0s 3:32 10% 0+0k 0+0io 0pf+0w
 
               (See  below  the "Environment Variables and Prede-
               fined Shell Variables"  sub-section  on  the  time
               variable.)
 
SunOS 5.6            Last change: 23 May 1997                  23
 
User Commands                                              csh(1)
 
     umask      [ value ]
               Display  the  file creation mask.  With value, set
               the file  creation  mask.   With  value  given  in
               octal,  the user can turn-off any bits, but cannot
               turn-on bits to  allow  new  permissions.   Common
               values  include  077,  restricting all permissions
               from everyone else; 002, giving complete access to
               the  group, and read (and directory search) access
               to others; or  022,  giving  read  (and  directory
               search)  but not write permission to the group and
               others.
 
     unalias pattern
               Discard aliases that match (filename substitution)
               pattern.  All aliases are removed by `unalias *'.
 
     unhash    Disable the internal hash tables for the path    and
               cdpath variables.
 
     unlimit [ -h ] [ resource  ]
               Remove  a  limitation on resource.  If no resource
               is specified, then all  resource  limitations  are
               removed.  See the description of the limit command
               for the list of resource names.
 
               -h   Remove corresponding hard   limits.   Only  the
                    privileged user may do this.
 
     unset      pattern
               Remove  variables whose names match (filename sub-
               stitution) pattern.  All variables are removed  by
               `unset  *';  this        has noticeably distasteful side
               effects.
 
     unsetenv variable
               Remove variable from  the  environment.   As  with
               unset, pattern matching is not performed.
 
     wait          Wait  for  background  jobs  to  finish (or for an
               interrupt) before prompting.
 
     while      (expr)
     ...
     end          While expr is true (evaluates to nonzero),  repeat
               commands  between  the  while and the matching end
               statement.  break and continue may be used to ter-
               minate  or  continue  the  loop  prematurely.  The
               while and end must appear  alone  on  their  input
               lines.   If  the  shell's  input is a terminal, it
               prompts for commands with  a  question-mark  until
               the  end  command is entered and then    performs the
               commands in the loop.
 
SunOS 5.6            Last change: 23 May 1997                  24
 
User Commands                                              csh(1)
 
     %[ job ] [ &       ]
               Bring the current or indicated job  to  the  fore-
               ground.   With the ampersand, continue running job
               in the background.
 
     @  [ var =expr ]
     @  [ var[n] =expr ]
               With no arguments,  display  the  values  for  all
               shell variables.  With arguments, set the variable
               var, or the n'th word in the     value of var, to  the
               value  that  expr  evaluates      to.  (If [n] is sup-
               plied,  both  var  and  its  n'th  component      must
               already exist.)
 
               If the expression contains the characters >, <, &,
               or |, then at least this  part   of  expr  must  be
               placed within parentheses.
 
               The  operators *=, +=, and so forth,     are available
               as in C.  The space separating the name  from  the
               assignment operator is optional.  Spaces are, how-
               ever, mandatory in separating components  of  expr
               that would otherwise be single words.
 
               Special postfix operators, ++ and --, increment or
               decrement name, respectively.
 
  Environment Variables and Predefined  Shell Variables
     Unlike the Bourne shell, the C shell maintains a distinction
     between   environment  variables,  which  are  automatically
     exported to processes it invokes, and shell variables, which
     are  not.   Both  types  of  variables are treated similarly
     under variable substitution.  The shell sets  the  variables
     argv,      cwd,     home, path, prompt, shell, and status  upon ini-
     tialization.  The shell copies the environment variable USER
     into  the shell variable user,     TERM into term, and HOME into
     home, and copies each back into the  respective  environment
     variable  whenever  the shell variables are reset.  PATH and
     path are similarly handled.  You need only set     path once  in
     the  .cshrc or .login file.  The environment variable PWD is
     set from cwd whenever the  latter  changes.   The  following
     shell variables have predefined meanings:
 
     argv                  Argument  list.  Contains the list of com-
                       mand line arguments supplied to  the  cur-
                       rent  invocation of the shell.  This vari-
                       able determines the  value  of  the  posi-
                       tional parameters $1, $2, and so on.
 
     cdpath          Contains  a  list  of  directories  to  be
                       searched by the cd, chdir, and  popd     com-
                       mands,  if  the  directory  argument  each
 
SunOS 5.6            Last change: 23 May 1997                  25
 
User Commands                                              csh(1)
 
                       accepts is not a subdirectory of the  cur-
                       rent directory.
 
     cwd                  The  full  pathname  of the current direc-
                       tory.
 
     echo                  Echo commands (after  substitutions)  just
                       before execution.
 
     fignore          A list of filename suffixes to ignore when
                       attempting filename completion.  Typically
                       the single word `.o'.
 
     filec                  Enable  filename completion, in which case
                       the CTRL-d character EOT and the ESC char-
                       acter have special significance when typed
                       in at the end of a terminal input line:
 
                       EOT  Print a list of  all  filenames  that
                            start with the preceding string.
                       ESC  Replace the preceding string with the
                            longest unambiguous extension.
 
     hardpaths          If set, pathnames in the  directory  stack
                       are  resolved  to contain no symbolic-link
                       components.
 
     histchars          A two-character string.  The first charac-
                       ter  replaces  !  as the history-substitu-
                       tion character.  The second  replaces  the
                       carat (^) for quick substitutions.
 
     history          The  number  of lines saved in the history
                       list.  A very large number may use up  all
                       of  the C shell's memory.  If not set, the
                       C shell saves only the  most  recent  com-
                       mand.
 
     home                  The  user's  home directory.  The filename
                       expansion of ~ refers to the value of this
                       variable.
 
     ignoreeof          If  set, the shell ignores EOF from termi-
                       nals.  This protects against  accidentally
                       killing a C shell by typing a CTRL-d.
 
     mail                  A  list  of files where the C shell checks
                       for mail.  If the first word of the  value
                       is  a number, it specifies a mail checking
                       interval in seconds (default 5 minutes).
 
     nobeep          Suppress   the   bell    during    command
 
SunOS 5.6            Last change: 23 May 1997                  26
 
User Commands                                              csh(1)
 
                       completion  when  asking  the  C  shell to
                       extend an ambiguous filename.
 
     noclobber          Restrict output redirection so that exist-
                       ing  files  are not destroyed by accident.
                       > redirections can only   be  made  to  new
                       files.   >>  redirections can only be made
                       to existing files.
 
     noglob          Inhibit filename  substitution.   This  is
                       most  useful  in  shell scripts once file-
                       names (if any) are obtained and no further
                       expansion is desired.
 
     nonomatch          Returns the filename substitution pattern,
                       rather than an error, if  the  pattern  is
                       not  matched.   Malformed  patterns  still
                       result in errors.
 
     notify          If set, the shell notifies you immediately
                       as jobs are completed, rather than waiting
                       until just before issuing a prompt.
 
     path                  The list of directories in which to search
                       for  commands.   path  is initialized from
                       the environment variable PATH, which     the C
                       shell  updates  whenever  path changes.  A
                       null word specifies the current directory.
                       The default is typically (/usr/bin .).  If
                       path     becomes  unset  only  full  pathnames
                       will execute.  An interactive C shell will
                       normally hash the contents of the directo-
                       ries  listed  after  reading  .cshrc,  and
                       whenever path is reset.  If      new  commands
                       are  added,  use  the  rehash  command  to
                       update the table.
 
     prompt          The string an interactive C shell  prompts
                       with.   Noninteractive  shells  leave  the
                       prompt variable unset.  Aliases and  other
                       commands  in the .cshrc file that are only
                       useful interactively, can be placed  after
                       the  following  test:  `if ($?prompt == 0)
                       exit', to reduce startup time  for  nonin-
                       teractive  shells.   A  !   in   the prompt
                       string is replaced by  the  current  event
                       number.   The  default prompt is hostname%
                       for mere mortals,  or  hostname#  for  the
                       privileged user.
 
                       The setting of $prompt has three meanings:
 
SunOS 5.6            Last change: 23 May 1997                  27
 
User Commands                                              csh(1)
 
                       $prompt  not  set            --   non-interactive
                       shell, test $?prompt.
 
                       $prompt  set  but        == ""   -- .cshrc       called
                       by the which(1) command.
 
                       $prompt set and != "" -- normal  interac-
                       tive shell.
 
     savehist          The  number of lines from the history list
                       that are saved in ~/.history when the user
                       logs  out.  Large values for savehist slow
                       down the C shell during startup.
 
     shell                  The file in which  the  C  shell  resides.
                       This  is  used in forking shells to inter-
                       pret files that have execute bits set, but
                       that are not executable by the system.
 
     status          The  status  returned  by  the most recent
                       command.   If  that   command   terminated
                       abnormally,  0200  is added to the status.
                       Built-in commands that  fail  return  exit
                       status  1; all other built-in commands set
                       status to 0.
 
     time                  Control automatic timing of commands.  Can
                       be  supplied  with one or two values.  The
                       first is the reporting  threshold  in  CPU
                       seconds.   The  second is a string of tags
                       and text  indicating  which  resources  to
                       report  on.   A  tag is a percent sign (%)
                       followed by  a  single  upper-case  letter
                       (unrecognized tags print as text):
 
                              %D   Average   amount  of  unshared
                                   data space used in  Kilobytes.
                              %E   Elapsed  (wallclock)  time   for
                                   the command.
                              %F   Page faults.
                              %I   Number of block  input  opera-
                                   tions.
                              %K   Average   amount  of  unshared
                                   stack space used in Kilobytes.
                              %M   Maximum  real memory used dur-
                                   ing execution of the  process.
                              %O   Number  of   block output opera-
                                   tions.
                              %P   Total CPU    time  --  U  (user)
                                   plus  S  (system) -- as a per-
                                   centage of E (elapsed) time.
                              %S   Number of seconds of CPU  time
 
 SunOS 5.6            Last change: 23 May 1997                  28
 
User Commands                                              csh(1)
 
                                   consumed   by  the  kernel  on
                                   behalf of the user's  process.
                              %U   Number  of   seconds of CPU time
                                   devoted to the user's process.
                              %W   Number of swaps.
                              %X   Average  amount of   shared mem-
                                   ory used in Kilobytes.
 
                       The default summary display  outputs  from
                       the  %U,  %S,  %E,       %P, %X, %D, %I, %O, %F,
                       and %W   tags, in that order.
 
     verbose          Display each command after history substi-
                       tution takes place.
 
  Large File Behavior
     See  largefile(5)  for the description of the behavior of csh
     when encountering files greater than or  equal  to  2  Gbyte
     (2**31 bytes).
 
FILES
     ~/.cshrc            Read  at  beginning of execution by each
                         shell.
     ~/.login            Read by login  shells  after  .cshrc  at
                         login.
     ~/.logout            Read by login shells at logout.
     ~/.history    Saved history for use at next login.
     /usr/bin/sh            The  Bourne shell, for shell scripts not
                         starting with a `#'.
     /tmp/sh*            Temporary file for `<<'.
     /etc/passwd            Source of home directories for  `~name'.
 
ATTRIBUTES
     See   attributes(5)   for   descriptions    of  the  following
     attributes:
 
     +---------------+-----------------+
     |ATTRIBUTE TYPE | ATTRIBUTE VALUE |
     +---------------+-----------------+
     |Availability   | SUNWcsu         |
     |CSI            | Enabled         |
     +---------------+-----------------+
SEE ALSO
     bc(1), echo(1),  login(1),  ls(1),  more(1),  ps(1),  sh(1),
     shell_builtins(1),  tset(1B),  which(1),  df(1M),   swap(1M),
     sysdef(1M), access(2),     exec(2), fork(2), pipe(2),      a.out(4),
     environ(4),          ascii(5),  attributes(5),  environ(5),        large-
     file(5), termio(7I)
 
DIAGNOSTICS
     You have stopped jobs.
          You attempted to exit the C  shell  with  stopped  jobs
 
SunOS 5.6            Last change: 23 May 1997                  29
 
User Commands                                              csh(1)
 
          under job control.  An immediate second attempt to exit
          will succeed, terminating the stopped jobs.
 
WARNINGS
     The use of setuid shell scripts is strongly discouraged.
 
NOTES
     Words can be no longer than 1024 bytes.  The  system  limits
     argument  lists  to  1,048,576  bytes.  However, the maximum
     number of arguments to a command for which  filename  expan-
     sion  applies  is 1706.  Command substitutions may expand to
     no more characters than are allowed in  the  argument  list.
     To  detect  looping, the shell restricts the number of alias
     substitutions on a single line to 20.
 
     When a command is restarted from a stop,  the  shell  prints
     the  directory  it  started in if this is different from the
     current directory; this can be misleading (that  is,  wrong)
     as the job may have changed directories internally.
 
     Shell  built-in  functions  are  not  stoppable/restartable.
     Command sequences of the form
     a  ; b ; c are     also not handled gracefully when  stopping  is
     attempted.   If  you  suspend b, the shell never executes  c.
     This is especially noticeable if the expansion results  from
     an  alias.   It  can  be  avoided by placing the sequence in
     parentheses to force it into a subshell.
 
     Control over terminal output after processes are started  is
     primitive; use the Sun Window system if you need better out-
     put control.
 
     Commands within loops, prompted for by ?,  are not placed  in
     the history        list.
 
     Control structures should be parsed rather than being recog-
     nized as built-in commands.  This would allow  control  com-
     mands  to  be placed anywhere, to be combined with |, and  to
     be used with & and ; metasyntax.
 
     It should be possible to use the : modifiers on  the  output
     of  command  substitutions.   There  are two problems with :
     modifier usage on variable substitutions:  not  all  of  the
     modifiers are available, and only one modifier per substitu-
     tion is allowed.
 
     The g (global) flag in history substitutions applies only  to
     the first match in each word, rather than all matches in all
     words.  The common text editors consistently do  the  latter
     when given the g flag in a substitution command.
 
SunOS 5.6            Last change: 23 May 1997                  30
 
User Commands                                              csh(1)
 
     Quoting  conventions  are  confusing.  Overriding the escape
     character to  force  variable  substitutions  within  double
     quotes  is counterintuitive and inconsistent with the Bourne
     shell.
 
     Symbolic links can fool the shell.   Setting  the  hardpaths
     variable alleviates this.
 
     It  is up to the user to manually remove all duplicate path-
     names accrued from using built-in commands as
          set path = pathnames
     or
          setenv PATH   pathnames
     more than once.  These often occur because a shell script or
     a  .cshrc  file  does  something  like `set path=(/usr/local
     /usr/hosts $path)' to ensure that the named directories  are
     in the pathname list.
 
     The  only  way  to  direct  the standard output and standard
     error separately is by invoking a subshell, as follows:
 
          example% (command > outfile)  >& errorfile
 
     Although robust enough for general use, adventures into  the
     esoteric  periphery  of  the  C  shell may reveal unexpected
     quirks.
 
     If you start csh as a login shell and  you  do     not  have  a
     .login  in  your  home  directory, then the csh reads in the
     /etc/.login.
 
     When the shell executes a shell script that attempts to exe-
     cute  a  non-existent command interpreter, the shell returns
     an erroneous diagnostic message that the shell  script  file
     does not exist.
 
BUGS
     As  of this writing, the time built-in     command does NOT com-
     pute the last 6 fields of output, rendering  the  output  to
     erroneously report the value "0" for these fields.
 
                    example %time ls -R
                    9.0u 11.0s  3:32 10%        0+0k 0+0io 0pf+0w
 
SunOS 5.6            Last change: 23 May 1997                  31

--------------7232EEEE8CDE47460EDEDF0D--




TUCoPS is optimized to look best in Firefox® on a widescreen monitor (1440x900 or better).
Site design & layout copyright © 1986-2014 AOH