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Perl Programming/Keywords/-r
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Perl -R -S Keywords
The -r keyword
-r is a file test that tests, if the file is readable by effective uid/gid.
It takes one argument, either a FILENAME, a FILEHANDLE, or a DIRHANDLE to test the associated file to see, if something is true about it. If the argument is omitted, it tests $_. -r returns 1 for true and an empty string for false. If the file doesn't exist or can't be examined, it returns undef and sets $! (errno).
Syntax
-r DIRHANDLE
-r EXPRESSION
-r FILEHANDLE
-r FILENAME
-r
Perl -R -S Keywords
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