NAME

Linux::Setns - Perl extension for switching the current prcoess namespace to another namespace pointed by a file descriptor.

SYNOPSIS

        use Linux::setns qw(setns CLONE_ALL CLONE_NEWIPC CLONE_NEWNET CLONE_NEWUTC);

        die "setns() requires root privileges\n" if $<;

        open my $FD, '<', "/proc/PID/ns/mnt" or die "setns(): unable to open FD\n";

        setns($FD, CLONE_ALL);
        # now your process is in the same namespace as the $FD you have supplied
        # in this case, you have to previously know what is the type of namespace of that $FD

        setns($FD, CLONE_NEWIPC);
        # Switch your current IPC namespace to the one pointed by $FD
        setns($FD, CLONE_NEWNET);
        # Switch your current Network namespace to the one pointed by $FD
        setns($FD, CLONE_NEWUTC);
        # Switch your current UTS namespace to the one pointed by $FD

DESCRIPTION

This trivial module provides interface to the Linux setns system call. It also provides the CLONE_* constants that are used to specify which kind of namespace you are entering. Also a new CLONE_ALL constat is provided so you can join/switch to any type of namespace.

The setns system call allows a process to 'join/switch' one of its namespaces to namespace pointed by a file descriptor(usually located in /proc/PID/ns/{ipc,mnt,net,pid,user,uts}).

Note: keep in mind that using CLONE_NEWIPC, CLONE_NEWNET or CLONE_NEWUTS will fail if the FD is not of that type.

RETRUN VALUE 1 on success 0 on failure

EXPORT

 setns                  - the subroutine

 CLONE_ALL              - flag that tells that the FD can be of any namespace type
 CLONE_NEWIPC   - when this flag is used the FD must be from a IPC namespace
 CLONE_NEWNET   - when this flag is used the FD must be from a Network namespace
 CLONE_NEWUTS   - when this flag is used the FD must be from a UTS namespace

SEE ALSO

setns(s) Linux man page.

AUTHOR

Marian HackMan Marinov, <hackman@cpan.org>

COPYRIGHT AND LICENSE

Copyright (C) 2016 by Marian HackMan Marinov

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.10.1 or, at your option, any later version of Perl 5 you may have available.