In the TCSH (also known as the C shell), you can check whether a directory is empty or not using the ls command and the test command. Here’s how:
if ( ! (`ls -A $dir 2>/dev/null`) ) then
echo "$dir is empty"
else
echo "$dir is not empty"
endif
In this example, the ls command lists the contents of the directory specified by the $dir variable. The -A option causes ls to list all files in the directory, including hidden files. The 2>/dev/null redirects error messages from the ls command to /dev/null, so that they are not displayed on the screen.
The output of the ls command is captured in a command substitution $(...), and the result is passed as an argument to the test command (! ( ... )). The test command returns true if its argument is an empty string, which means that the directory is empty.
If the directory is empty, the message “$dir is empty” is displayed. If the directory is not empty, the message “$dir is not empty” is displayed.