source: trunk/third/perl/plan9/perlplan9.pod @ 10724

=head1 NAME

perlplan9 - Plan 9-specific documentation for Perl

=head1 DESCRIPTION

These are a few notes describing features peculiar to
Plan 9 Perl. As such, it is not intended to be a replacement
for the rest of the Perl 5 documentation (which is both 
copious and excellent). If you have any questions to 
which you can't find answers in these man pages, contact 
Luther Huffman at lutherh@stratcom.com and we'll try to 
answer them.

=head2 Invoking Perl

Perl is invoked from the command line as described in 
L<perl>. Most perl scripts, however, do have a first line 
such as "#!/usr/local/bin/perl". This is known as a shebang 
(shell-bang) statement and tells the OS shell where to find 
the perl interpreter. In Plan 9 Perl this statement should be 
"#!/bin/perl" if you wish to be able to directly invoke the 
script by its name.
     Alternatively, you may invoke perl with the command "Perl"
instead of "perl". This will produce Acme-friendly error
messages of the form "filename:18".

Some scripts, usually identified with a *.PL extension, are 
self-configuring and are able to correctly create their own 
shebang path from config information located in Plan 9 
Perl. These you won't need to be worried about.

=head2 What's in Plan 9 Perl

Although Plan 9 Perl currently only  provides static 
loading, it is built with a number of useful extensions. 
These include Opcode, FileHandle, Fcntl, and POSIX. Expect 
to see others (and DynaLoading!) in the future.

=head2 What's not in Plan 9 Perl

As mentioned previously, dynamic loading isn't currently 
available nor is MakeMaker. Both are high-priority items.

=head2 Perl5 Functions not currently supported

Some, such as C<chown> and C<umask> aren't provided 
because the concept does not exist within Plan 9. Others,
such as some of the socket-related functions, simply
haven't been written yet. Many in the latter category 
may be supported in the future.

The functions not currently implemented include:

    chown, chroot, dbmclose, dbmopen, getsockopt, 
    setsockopt, recvmsg, sendmsg, getnetbyname, 
    getnetbyaddr, getnetent, getprotoent, getservent, 
    sethostent, setnetent, setprotoent, setservent, 
    endservent, endnetent, endprotoent, umask

There may be several other functions that have undefined 
behavior so this list shouldn't be considered complete.

=head2 Signals

For compatibility with perl scripts written for the Unix 
environment, Plan 9 Perl uses the POSIX signal emulation
provided in Plan 9's ANSI POSIX Environment (APE). Signal stacking
isn't supported. The signals provided are:

    SIGHUP, SIGINT, SIGQUIT, SIGILL, SIGABRT,
    SIGFPE, SIGKILL, SIGSEGV, SIGPIPE, SIGPIPE, SIGALRM, 
    SIGTERM, SIGUSR1, SIGUSR2, SIGCHLD, SIGCONT,
    SIGSTOP, SIGTSTP, SIGTTIN, SIGTTOU

=head1 BUGS

"As many as there are grains of sand on all the beaches of the 
world . . ." - Carl Sagan

=head1 Revision date

This document was revised 09-October-1996 for Perl 5.003_7.

=head1 AUTHOR

Luther Huffman,    lutherh@stratcom.com