.login and .cshrc files" 1070 is the use of conditionals (if statements). This article explains the syntax of if statements. Article 47.4of explains the syntax of the expressions you can test with an if.
The if command is used to 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 after the else if
and continue checking).
For example, the following if clause will
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
For more examples, see article 47.4.
- from O'Reilly & Associates' UNIX in a Nutshell (SVR4/Solaris)