-X

-X

-X FILEHANDLE

-X EXPR

-X DIRHANDLE

-X

A file test, where X is one of the letters listed below. This unary operator takes one argument, either a filename, a filehandle, or a dirhandle, and tests the associated file to see if something is true about it. If the argument is omitted, tests $_ , except for -t , which tests STDIN. Unless otherwise documented, it returns 1 for true and '' for false. If the file doesn't exist or can't be examined, it returns undef and sets $! (errno). Despite the funny names, precedence is the same as any other named