set(1)                                                             User Commands                                                            set(1)

NAME

       set, unset, setenv, unsetenv, export - shell built-in functions to determine the characteristics for environmental variables of the current
       shell and its descendents

SYNOPSIS

   sh
       set  [--aefhkntuvx [argument]]...

       unset [name...]

       export [name...]

   csh
       set [ var [ = value]]

       set var [n] = word

       unset pattern

       setenv [ VAR [word]]

       unsetenv variable

   ksh
       set [+-abCefhkmnopstuvx]  [+-o option]... [+-A name] [arg...]

       unset [-f] name...

       **export  [ name [=value]]...

       **export [-p]

DESCRIPTION

   sh
       The set built-in command has the following options:

       --       Does not change any of the flags. This option is useful in setting $1 to -.

       -a       Marks variables which are modified or created for export.

       -e       Exits immediately if a command exits with a non-zero exit status.

       -f       Disables file name generation.

       -h       Locates and remembers function commands as functions are defined. Function commands are normally located when the function is exe-
                cuted.

       -k       All keyword arguments are placed in the environment for a command, not just those that precede the command name.

       -n       Reads commands but does not execute them.

       -t       Exits after reading and executing one command.

       -u       Treats unset variables as an error when substituting.

       -v       Prints shell input lines as they are read.

       -x       Prints commands and their arguments as they are executed.

       Using  +  rather  than - causes these flags to be turned off. These flags can also be used upon invocation of the shell. The current set of
       flags can be found in $-. The remaining arguments are positional parameters and are assigned, in order, to $1, $2, .... If no arguments are
       given the values of all names are printed.

       For each name, unset removes the corresponding variable or function value. The variables PATH, PS1, PS2, MAILCHECK, and IF cannot be unset.

       With the export built-in, the given names are marked for automatic export to the environment of subsequently executed commands. If no argu-
       ments are given, variable names that have been marked for export during the current shell's execution are listed. Function  names  are  not
       exported.

   csh
       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.

       unset removes variables whose names match (filename substitution) pattern. All variables are removed by `unset *'.

       With no arguments, setenv displays all environment variables. With the VAR argument, setenv sets the environment variable VAR  to an  empty
       (null)  value.   (By  convention,  environment  variables are normally given upper-case names.) With both VAR and word arguments specified,
       setenv sets VAR to word, which must be either a single word or a quoted string. The PATH variable can take multiple word  arguments,  sepa-
       rated  by  colons  (see  EXAMPLES).  The  most commonly used environment variables, USER, TERM, and PATH, are automatically imported to and
       exported from the csh variables user, term, and path. Use setenv if you need to change these variables. 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. See environ(5) for descriptions of these environment variables.

       unsetenv removes variable from the environment. As with unset, pattern matching is not performed.

   ksh
       The flags for the set built-in have meaning as follows:

       -A       Array assignment. Unsets the variable name and assigns values sequentially from the list arg. If +A is used, the variable name  is
                not unset first.

       -a       All subsequent variables that are defined are automatically exported.

       -b       Causes the shell to notify the user asynchronously of background job completions.

       -C       Prevents  existing  files from being overwritten by the shell's > redirection operator. The >| redirection operator overrides this
                noclobber option for an individual file.

       -e       If a command has a non-zero exit status, executes the ERR trap, if set, and exits. This mode is disabled while reading profiles.

       -f       Disables file name generation.

       -h       Each command becomes a tracked alias when first encountered.

       -k       All variable assignment arguments are placed in the environment for a command, not just those that precede the command name.

       -m       Background jobs run in a separate process group and a line prints upon completion. The exit status of background jobs is  reported
                in a completion message. On systems with job control, this flag is turned on automatically for interactive shells.

       -n       Reads commands and checks them for syntax errors, but does not execute them. Ignored for interactive shells.

       +o        Writes  the  current  option  stettings to standard output in a format that is suitable for reinput to the shell as commands that
                achieve the same option settings.

       -o optionThe option argument can be one of the following option names:

                allexport       Same as -a.

                errexit         Same as -e.

                bgnice          All background jobs are run at a lower priority. This is the default mode. emacs Puts you in an  emacs  style  in-
                                line editor for command entry.

                gmacs           Puts you in a gmacs style in-line editor for command entry.

                ignoreeof       The shell does not exit on end-of-file. The command exit must be used.

                keyword         Same as -k.

                markdirs        All directory names resulting from file name generation have a trailing / appended.

                monitor         Same as -m.

                noclobber       Prevents  redirection  operator > from truncating existing files. Requires the >| operator to truncate a file when
                                turned on. Same as -C.

                noexec          Same as -n.

                noglob          Same as -f.

                nolog           Does not save function definitions in history file.

                notify          Same as -b.

                nounset         Same as -u.

                privileged      Same as -p.

                verbose         Same as -v.

                trackall        Same as -h.

                vi              Puts you in insert mode of a vi style in-line editor until you hit escape character 033. This puts you in  control
                                mode. A return sends the line.

                viraw           Each character is processed as it is typed in vi mode.

                xtrace          Same as -x.

       If no option name is supplied then the current option settings are printed.

       -p       Disables  processing of the $HOME/.profile file and uses the file /etc/suid_profile instead of the ENV file. This mode is on when-
                ever the effective uid is not equal to the real uid, or when the effective gid is not equal to the  real  gid.  Turning  this  off
                causes the effective uid and gid to be set to the real uid and gid.

       -s       Sorts the positional parameters lexicographically.

       -t       Exits after reading and executing one command.

       -u       Treats unset parameters as an error when substituting.

       -v       Prints shell input lines as they are read.

       -x       Prints commands and their arguments as they are executed.

       -        Turns off -x and -v flags and stops examining arguments for flags.

       -        Does  not  change  any  of the flags. This option is useful in setting $1 to a value beginning with -. If no arguments follow this
                flag then the positional parameters are unset.

       Using + rather than - causes these flags to be turned off. These flags can also be used upon invocation of the shell. The  current  set  of
       flags  can  be  found in $-. Unless -A is specified, the remaining arguments are positional parameters and are assigned, in order, to $1 $2
       .... If no arguments are given then the names and values of all variables are printed on the standard output.

       The variables given by the list of names are unassigned, that is, their values and attributes are  erased.  readonly  variables  cannot  be
       unset.  If the -f flag is set, then the names refer to function names. Unsetting ERRNO, LINENO, MAILCHECK, OPTARG, OPTIND, RANDOM, SECONDS,
       TMOUT, and _ removes their special meaning even if they are subsequently assigned.

       When using unset, the variables given by the list of names are unassigned, i.e., their values and attributes are erased. readonly variables
       cannot  be  unset. If the -f, flag is set, then the names refer to function names. Unsetting ERRNO, LINENO, MAILCHECK, OPTARG, OPTIND, RAN-
       DOM, SECONDS, TMOUT, and _ removes their special meaning even if they are subsequently assigned.

       With the export built-in, the given names are marked for automatic export to the environment of subsequently-executed commands.

       When -p is specified, export writes to the standard output the names and values of all exported variables in the following format:

       "export %s=%s
", name, value

       if name is set, and:

       "export %s
", name

       if name is unset.

       The shell formats the output, including the proper use of quoting, so that it is suitable for reinput to the shell as commands that achieve
       the same exporting results, except for the following:

       1.  Read-only variables with values cannot be reset.

       2.  Variables  that were unset at the time they were output are not reset to the unset state if a value is assigned to the variable between
           the time the state was saved and the time at which the saved output is reinput to the shell.

       On this man page, ksh(1) commands that are preceded by one or two * (asterisks) are treated specially in the following ways:

       1.  Variable assignment lists preceding the command remain in effect when the command completes.

       2.  I/O redirections are processed after variable assignments.

       3.  Errors cause a script that contains them to abort.

       4.  Words, following a command preceded by ** that are in the format of a variable assignment, are expanded with the same rules as a  vari-
           able  assignment.  This means that tilde substitution is performed after the = sign and word splitting and file name generation are not
           performed.

EXAMPLES

   csh
       The following example sets the PATH variable to search for files in the /bin, /usr/bin, /usr/sbin, and /usr/ucb/bin  directories,  in  that
       order:

       setenv PATH "/bin:/usr/bin:/usr/sbin:usr/ucb/bin"

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE         |      ATTRIBUTE VALUE        |
       +-----------------------------+-----------------------------+
       |Availability                 |SUNWcsu                      |
       +-----------------------------+-----------------------------+

SEE ALSO

       csh(1), ksh(1), read(1), sh(1), typeset(1), attributes(5), environ(5)

SunOS 5.10                                                          13 Jul 2004                                                             set(1)