Name
if
Synopsis
if
Description
Begin a conditional statement. The simple format is:
if (expr
)cmd
There are three other possible formats, shown side-by-side:
if (expr
) then if (expr
) then if (expr
) thencmds
cmds1
cmds1
endif else else if (expr
) thencmds2
cmds2
endif elsecmds3
endif
In the simplest form, execute cmd if expr is true; otherwise do nothing (redirection still occurs; this is a bug). In the other forms, execute one or more commands. If expr is true, continue with the commands after then; if expr is false, branch to the commands after else (or branch to after the else if and continue checking). For more examples, see Section 8.5 earlier in this chapter, shift, or while.
Example
Take a default action if no command-line arguments are given:
if ($#argv == 0) then
echo "No filename given. Sending to Report."
set outfile = Report
else
set outfile = $argv[1]
endif
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