Question

use IPC::Open3;

local(*A, *B, *C);

my $cmd = \&run;
my @args = ();
my $childpid = open3(*A, *B, *C, $cmd, @args);
print A "stuff\n";
close(A); 
my @outlines = <B>; 
my @errlines = <C>; 
print "STDOUT:\n", @outlines, "\n";
print "STDERR:\n", @errlines, "\n";
close B;
close C;
waitpid($childpid, 0);
if ($?) {
    print "That child exited with wait status of $?\n";
}

sub run {

}

It’s reporting:

STDERR:
sh: -c: line 0: syntax error near unexpected token `0x67bc50'
sh: -c: line 0: `CODE(0x67bc50)'

Why?

Answer 1

Looks like $cmd should be an actual shell command, not a perl subroutine. The error message comes from perl trying to execute the stringified reference to the sub, CODE(0x67bc50) in the shell.

To get the return value from the subroutine as the command, use $cmd->(). That might not do what I think you expect it to, though.