! Aware to Perl: How do I close a file descriptor by number?

RocketAware > Perl >

How do I close a file descriptor by number?

Tips: Browse or Search all pages for efficient awareness of Perl functions, operators, and FAQs.

Home

Search Perl pages

Subjects

By activity
Professions, Sciences, Humanities, Business, ...

User Interface
Text-based, GUI, Audio, Video, Keyboards, Mouse, Images,...

Text Strings
Conversions, tests, processing, manipulation,...

Math
Integer, Floating point, Matrix, Statistics, Boolean, ...

Processing
Algorithms, Memory, Process control, Debugging, ...

Stored Data
Data storage, Integrity, Encryption, Compression, ...

Communications
Networks, protocols, Interprocess, Remote, Client Server, ...

Hard World
Timing, Calendar and Clock, Audio, Video, Printer, Controls...

File System
Management, Filtering, File & Directory access, Viewers, ...

How do I close a file descriptor by number?

This should rarely be necessary, as the Perl close() function is to be used for things that Perl opened itself, even if it was a dup of a numeric descriptor, as with MHCONTEXT above. But if you really have to, you may be able to do this:

    require 'sys/syscall.ph';
    $rc = syscall(&SYS_close, $fd + 0);  # must force numeric
    die "can't sysclose $fd: $!" unless $rc == -1;

Source: Perl FAQ: Files and Formats
Copyright: Copyright (c) 1997 Tom Christiansen and Nathan Torkington.

Next: Why can't I use "C:\temp\foo" in DOS paths? What doesn't `C:\temp\foo.exe` work?

Previous: How do I dup() a filehandle in Perl?

(Corrections, notes, and links courtesy of RocketAware.com)

[Overview Topics]

Up to: File Access

Rapid-Links: Search | About | Comments | Submit Path: RocketAware > Perl > perlfaq5/How_do_I_close_a_file_descriptor.htm