Name
if
Synopsis
if
Begin a conditional statement. The simple format is:
if (expr
)cmd
There are three other possible formats, shown side by side:
Example 1 |
Example 2 |
Example 3 |
---|---|---|
if ( |
if ( |
if ( |
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 21.5 earlier
in this chapter, as well as the entries 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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