Linux and Unix set command
In C shell sets the value of an environment variable.
set [--] [-a] [-e] [-f] [-h] [-k] [-m] [-n] [-p] [-s] [-t] [-u] [-v] [-x] [ -o option ] [ -A name ] [arg]
|--||Do not change any of the flags; useful in setting $1 to -.|
|-a||Mark variables which are modified or created for export.|
|-e||Exit immediately if a command exits with a nonzero exit status.|
|-f||Disable file name generation.|
|-h||Locate and remember function commands as functions are defined (function commands are normally located when the function is executed).|
|-k||All keyword arguments are placed in the environment for a command, not just those that
precede the command name.
|-m||Background jobs will run in a separate process group and a line will print 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||Read commands but do not execute them.|
|-p||Disables processing of the $HOME/.profile file and uses the file /etc/suid_profile instead of the ENV file. This mode is on whenever 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||Sort the positional parameters lexicographically.|
|-t||Exit after reading and executing one command.|
|-u||Treat unset variables as an error when substituting.|
|-v||Print shell input lines as they are read.|
|-x||Print commands and their arguments as they are executed.|
|-o option||The following argument can be one of the following option names:
|-A name||Array assignment. Unset the variable name and assign values sequentially from the list arg. If +A is used, the variable name is not unset first.|
* Using + rather than - causes these flags to be turned off.
setenv PATH "/bin:/usr/bin:/usr/sbin:ucb/bin"
Sets the environment path to search for files in the /bin, /usr/bin, /usr/sbin and usb/bin directory.