csh/C shell scripts: if statement syntax
Posted by Rex in csh shell scripting
Conditional expressions give programs life. The ability to branch makes shell scripts powerful. This recipe shows the basic if then else structure for csh, the C shell.
Basic if statement syntax:
if (condition) then
commands
endif
The addition of one or more else keywords offers additional flexibility:
if (condition) then
commands
else if (other condition) then
commands
else
commands
endif
The Conversation
Follow the reactions below and share your own thoughts.
November 07, 2008 at 6:08 pm, Dan said:
test for the existence of a variable using
if ($?LD_LIBRARY_PATH == 0) then
setenv LD_LIBRARY_PATH /usr/lib;
endif
March 11, 2009 at 8:53 pm, Dan said:
A variation of the above would be:
if ( ! ${?LD_LIBRARY_PATH} ) then
setenv LD_LIBRARY_PATH /usr/lib
endif
Use the {} around variables as a habit since the variable names can often interfere with shell syntax.
The semicolon at the end is ignored.
March 11, 2009 at 8:51 pm, Dan said:
Without concrete examples of how the syntax is actually used, this is almost useless information.
December 14, 2009 at 3:23 pm, Paul said:
Almost? More like completely…
March 23, 2011 at 3:50 pm, Chisimobi said:
need more examples
March 23, 2011 at 3:50 pm, Chisim_obi said:
need more examples