I'm having a problem with perl returning incorrect success flags back to the unix shell, after issuing a back tick or qx command, and then attempting to die.

This code should die with an error, and return a failure to the shell. 

#!/usr/bin/perl -I/usr/local/dcvp/bin
use strict;
my $output = qx(asasas 2>&1);  ### Non-existent system call to force e
+rror
#$? = 0; ### This fails correctly if we reset $? but reports success o
+therwise
die " *** THIS SHOULD FAIL *** ";
print "At least we don't see this message...";

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Unfortunately it doesn't, I get this output: 
$ test3.pl && echo success  

sh: asasas: not found
 *** THIS SHOULD FAIL ***  at test3.pl line 5.
success

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This is only a problem on 5.04, 5.05 and later is fine.

I'm curious if anyone had encountered this before because it's causing shell scripts that rely on die/croak reporting errors correctly to fail.

We can work around it by resetting $? to 0 immediately after the system call.

Upgrading would fix this but we have some old xs API's that may not re-compile correctly under the new version. I know that 5.04 is reported to be unstable on solaris so I would *like* to upgrade. However, upgrading the production box will take a lot of effort to convince the clients and system administrators, so if anyone knows of any compelling bugs that they can point me at, I'd be grateful.

I believe this may be a logged bug because it's such an old version of perl, but if no-one has heard of this I'll submit it.

The perl version details are: 

perl -V
Summary of my perl5 (5.0 patchlevel 4 subversion 4) configuration:
  Platform:
    osname=solaris, osvers=2.6, archname=sun4-solaris
    uname='sunos cairnpapple 5.6 generic sun4u sparc sunw,ultra-4 '
    hint=recommended, useposix=true, d_sigaction=define
    bincompat3=y useperlio=undef d_sfio=undef
  Compiler:
    cc='cc', optimize='-O', gccversion=2.7.2.3
    cppflags=''
    ccflags =''
    stdchar='unsigned char', d_stdstdio=define, usevfork=false
    voidflags=15, castflags=0, d_casti32=define, d_castneg=define
    intsize=4, alignbytes=8, usemymalloc=y, prototype=define
  Linker and Libraries:
    ld='cc', ldflags =''
    libpth=/lib /usr/lib /usr/ccs/lib
    libs=-lsocket -lnsl -ldl -lm -lc -lcrypt
    libc=/lib/libc.so, so=so
    useshrplib=false, libperl=libperl.a
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' '
    cccdlflags='-fpic', lddlflags='-G'


Characteristics of this binary (from libperl):
  Built under solaris
  Compiled at Dec 10 1998 12:51:04
  @INC:
    /opt/gnu/lib/perl5/sun4-solaris/5.00404
    /opt/gnu/lib/perl5
    /opt/gnu/lib/perl5/site_perl/sun4-solaris
    /opt/gnu/lib/perl5/site_perl
    .

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In reply to Bug in Perl 5.04 with return value to shell from die, after using backticks or qx by Mungbeans

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