I had a bunch of thoughts about this but rather than write a longwinded post, I thought a little code would demonstrate better. (Untested.)
package Shell::DWIM;
use warnings;
use strict;
our ($RUN_ERROR, $OS_ERR);
*OS_ERROR = $^O =~ m{VMS|MSWin|OS/2} ? \$^E : \$!;
sub sysdwim {
local $@;
my $retval = eval { system @_ };
if ($retval == 0) {
$RUN_ERROR = undef;
return 1;
}
$RUN_ERROR =
$? > 0 ? $? : # non-zero exit code from program
$? == -1 ? "$OS_ERR" : # couldn't launch program for some rea
+son
$@ ? $@ : # eval failed
"system() failed with unknown error";
return;
}
sub import {
my $pkg = (caller)[0];
*{$pkg . ($_[0] eq 'override' ? "::system" : "::sysdwim")} = \&sys
+dwim;
*{$pkg . "::RUN_ERROR"} = \$RUN_ERROR;
}
1;
I'll gladly elaborate if any of my intentions are unclear. This isn't optimal either; it'd be perfect for my taste if it was possible to do a lexical no Shell:DWIM; as well, but I haven't gotten so far in Perl yet.
Makeshifts last the longest.
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