Path: utzoo!attcan!uunet!cs.utexas.edu!sdd.hp.com!usc!elroy.jpl.nasa.gov!jpl-devvax!lwall
From: lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall)
Newsgroups: comp.lang.perl
Subject: Re: Long function names (installation)
Message-ID: <8585@jpl-devvax.JPL.NASA.GOV>
Date: 3 Jul 90 21:02:22 GMT
References: <1990Jul3.001958.19915@agate.berkeley.edu>
Reply-To: lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall)
Organization: Jet Propulsion Laboratory, Pasadena, CA
Lines: 149

In article <1990Jul3.001958.19915@agate.berkeley.edu> raymond@math.berkeley.edu (Raymond Chen) writes:
: Has anyone succeeded in bringing up perl on machines which limit
: external identifiers to 8 characters?  Perl uses the names do_split
: and do_splice, which both become _do_spli after truncation.
: 
: I changed do_splice to do_splce in eval.c and dolist.c, and that seemed
: to work; nevertheless, I'm afraid that there might be some other collisions
: that weren't caught by the regressions.

There's also potential problems with do_exec{,free}, localiz{e,ing} and
origarg{c,v}.

: (Any chance Larry'll add this warning to the README?)

Nah, I'll just fix 'em.

: Also, is anybody working on porting perl to OS/2?  I figure I'll use
: Diomidis' MS-DOS version as a base, but I'd like to know if anybody
: else has tackled the task already.

Several people have newer versions of that, so you probably want one
of them.

: $_="-|";open _||print"creaJklrnue  osrhptt,aeh ";while(<_>){$}=5;s/(.{$}})(.)/(print$2),$1/eg while--$};print;}

Truly perverse.

Larry

P.S.  Here's the script I used to check conflicts:

#!/usr/bin/perl

$xname = shift;

open(NM,"nm -g $xname|") || die "Can't run nm: $!\n";

while (<NM>) {
    ($addr, $type, $name) = split(/\s+/);
    next if length($name) < 8;
    ($pre,$post) = unpack('a8a100',$name);
    if ($pre eq $lastpre) {
	if ($lastname ne '') {
	    print "\n",$lastname,"\n";
	}
	print $name,"\n";
	$lastname = '';
    }
    else {
	$lastname = $name;
	$lastpre = $pre;
    }

}

I have a fancier one that will check the sources.  It goes like this:

#!/usr/bin/perl

$CRITLEN = 7;
$CRITPAT = "a$CRITLEN a100";

while ($ARGV[0] =~ /^-/) {
    $_ = shift;
    if (/^-D(.*)/) {
	$defines .= " -D" . ($1 ? $1 : shift);
    }
    elsif (/^-I(.*)/) {
	$includes .= " -I" . ($1 ? $1 : shift);
    }
    elsif (/^-v/) {
	$verbose++;
    }
    else {
	die "Unrecognized switch: $_\n";
    }
}

open(LOC, ">/tmp/uniqid$$") || die "Can't create /tmp/uniqid$$: $!\n";

foreach $file (@ARGV) {
    print STDERR "$file\n" if $verbose;
    open(CPP,"cc -E $defines $includes $file|") || die "Can't run cpp: $!\n";
    $line = 2;

    while (<CPP>) {
	++$line;
	if (/^#/) {
	    next unless /^# \d/;
	    ($junk,$newline,$filename) = split;
	    $filename =~ s/"//g;
	    if ($stack[$#stack] eq $filename) {
		$line = $newline-1;
		next;
	    }
	    if ($stack[$#stack-1] eq $filename) {
		$line = pop(@lines)-1;
		pop(@stack);
	    }
	    else {
		push(@lines,$line);
		$line = $newline;
		push(@stack,$filename);
	    }
	}
    }
    else {
	@words = split(/\W+/,$_);
	shift(@words) if $words[0] eq '';
	foreach $word (@words) {
	    next if length($word) < $CRITLEN;
	    ($pre,$post) = unpack($CRITPAT,$word);
	    print LOC "$pre $post $filename $line\n";
	    $mapping = $mapping{$pre};
	    if (defined $mapping) {
		next if $mapping eq $post;
		$conflicts{$pre}++;		# Bingo!
		print STDERR "Found $pre$mapping vs $pre$post\n" if $verbose;
	    }
	    else {
		$mapping{$pre} = $post;
	    }
	}
    }
    close CPP;
    $line = 0;
}
close LOC;

@conflicts = sort keys(%conflicts);
if (@conflicts) {
    print "Conflicts with ",int(@conflicts)," prefixes\n";
    open(LOC, "/tmp/uniqid$$") || die "Can't reopen /tmp/uniqid$$: $!\n";
    while (<LOC>) {
	($pre,$post,$file,$line) = split(/ /);
	next unless $conflicts{$pre};
	chop($line);
	$tale{$pre} .= <<EOF unless $seen{$_}++;
$pre$post \toccurs in file $file at line $line.
EOF
    }
    close LOC;
    foreach $pre (@conflicts) {
	print "\nConflicts with $pre*:\n";
	print $tale{$pre};
    }
}

unlink "/tmp/uniqid$$";