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Perl Programming/Keywords/-p
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Perl -o -R Keywords
The -p keyword
-p is a file test that tests, if the file is a named pipe (FIFO), or filehandle is a pipe.
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 $_. -p 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
-p DIRHANDLE
-p EXPRESSION
-p FILEHANDLE
-p FILENAME
-p
Perl -o -R Keywords
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