ikegami, could you please explain what is going on here: 
> perl -wle '
$SIG{CHLD}="IGNORE";
$! = 33;
print system("ls -d .");
print -+-$!;
print $!;
print -+-$!'
.
-1
33
No child processes
10

[download]

It seems that string-ifying "$!" changes its value.

In reply to Re^2: system function is returning status -1 when running a unix command by repellent
in thread system function is returning status -1 when running a unix command by elf_firein

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