Works fine on Win2K

C:\>type test.pl
# grab the first ENV var name we find
for ( keys %ENV ) { $key = $_; last; }
# reset ENV var
print "Resetting $key, was $ENV{$key}\n";
$ENV{$key} = 'new value';
# fork
my $pid = fork();
# confess
print $pid ? "Parent has $key:$ENV{$key}\n" : "Child has $key:$ENV{$ke
+y}\n";


C:\>perl test.pl
Resetting PROMPT, was $P$G
Parent has PROMPT:new value
Child has PROMPT:new value

C:\>
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And on Redhat 7.3

[root@www root]# cat test.pl
# grab the first ENV var name we find
for ( keys %ENV ) { $key = $_; last; }
# reset ENV var
print "Resetting $key, was $ENV{$key}\n";
$ENV{$key} = 'new value';
# fork
my $pid = fork();
# confess
print $pid ? "Parent has $key:$ENV{$key}\n" : "Child has $key:$ENV{$ke
+y}\n";

[root@www root]# perl test.pl
Resetting _, was /usr/bin/perl
Parent has _:new value
Child has _:new value
[root@www root]#
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cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

Hmm, thanks. Your test works fine for me also. I think there must be another problem. Basically, the LD_LIBRARY_PATH of the parent shell points at libxml (C library) v2.4.22, whereas my Perl program uses a Lib::XML which only works with libxml v2.4.24 and above. So, in my Perl program, I set LD_LIBRARY_PATH to libxml v2.4.24 in a BEGIN block. However, this does not seem to be having the desired effect. Maybe I am missing something... Cheers Kevin

Ah, LD_LIBRARY_PATH is a "special" variable. Setting it once your program has started (even in a BEGIN block) is usually too late.

Some previous discussion on this, with a particularly illuminating reply from good brother tye, can be found at programatically setting the LD_LIBRARY_PATH. Searching for LD_LIBRARY_PATH will lead you to the others.

It might be too late. The loader that loaded perl is probably the same loader that's loading your shared libraries. It has already initialized and is no longer looking for that environment variable. You probably have to set the variable before invoking perl.

---
print map { my ($m)=1<<hex($_)&11?' ':'';
$m.=substr('AHJPacehklnorstu',hex($_),1) }
split //,'2fde0abe76c36c914586c';
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"Setting a value in %ENV changes the environment for both your process and child processes..."

jdporter
The 6th Rule of Perl Club is -- There is no Rule #6.

Nope, I only wanted to change the current process env. People seem pretty confident that you can do this. (So was I until just now!!) As discussed in reply above, I will just have to work out what else is wrong with my setting LD_LIBRARY_PATH for XML::LibXML. Cheers Kevin

Perhaps you should have shown some code.
If you're doing something like

  $ENV{'LD_LIBRARY_PATH'} = '/...';
  use XML::LibXML;
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then the problem may be that the envar isn't getting set until after the library gets loaded. In which case, try

  BEGIN { $ENV{'LD_LIBRARY_PATH'} = '/...'; }
  use XML::LibXML;
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jdporter
The 6th Rule of Perl Club is -- There is no Rule #6.

That sentence in perlvar does not mean "changing %ENV only changes the environment of all children", it's more like "note that this will change the envirnonment of all your children".

Relax and test it, %ENV represents the current environmental variables of your process, without caveats.

#!/usr/bin/perl

$ENV{FOO} = 1;

print "\$ENV{FOO} is $ENV{FOO} still\n";

exec( '/usr/bin/env' );
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The output of env will also mention "FOO" being "1".

Ok, thanks. That's what I thought. I must be missing something else then (see reply above). Will reply if/when I find out!