fcntl
fcntl filehandle, function, arg
Calls the file control
function
(with the function-specific
arg
) to use on the file or device
opened with filehandle
. fcntl
calls Unix’s fcntl
function (not available on Win32
platforms). If the function is not implemented, the program exits
with a fatal error. fcntl
sets
file descriptors for a filehandle. This built-in command is usable
when you use the Fcntl module in the standard distribution:
use Fcntl;
This module imports the correct
function
definitions. See the
description of the Fcntl module in Chapter 8.
The return value of fcntl
(and ioctl
) is as
follows:
Thus Perl returns true on success and false on failure, yet you can still easily determine the actual value returned by the operating system.
3.147.60.63