- Revision date
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 email@example.com and we'll try to answer them.
Perl is invoked from the command line as described in 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.
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.
What's not in Plan 9 Perl
As mentioned previously, dynamic loading isn't currently available nor is MakeMaker. Both are high-priority items.
Perl5 Functions not currently supported
Some, such as
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, firstname.lastname@example.org