perlplan9 - Plan 9-specific documentation for Perl
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 firstname.lastname@example.org and we'll try to answer them.
Perl is invoked from the command line as described in the perl manpage. 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.
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.
As mentioned previously, dynamic loading isn't currently available nor is MakeMaker. Both are high-priority items.
Some, such as chown and 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.
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
``As many as there are grains of sand on all the beaches of the world . . .'' - Carl Sagan
This document was revised 09-October-1996 for Perl 5.003_7.
Luther Huffman, email@example.com
If rather than formatting bugs, you encounter substantive content errors in these documents, such as mistakes in the explanations or code, please use the perlbug utility included with the Perl distribution.