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Perl Programming/Keywords/-S
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Perl -r -s Keywords
The -S keyword
-S is a file test that tests, if the file is a socket.
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 $_. -S 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
-S DIRHANDLE
-S EXPRESSION
-S FILEHANDLE
-S FILENAME
-S
Perl -r -s Keywords
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