How Perl Maps error no. to error string

perl_lover has asked for the wisdom of the Perl Monks concerning the following question:

$\ = "\n";
for($!=0;$!<=87;$!++) {
    print $!;
}
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This code prints all the error string. How does Perl maps this errorno. to error string ?
update : I am running perl, v5.6.1 on a freeBSD box

Comment on How Perl Maps error no. to error string Download Code

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Re: How Perl Maps error no. to error string by ikegami (Patriarch) on Aug 17, 2006 at 05:03 UTC
`$!` is probably `errno` when used in numerical context, and `strerror(errno)` when used in string context.	[reply] [d/l] [select]
Re: How Perl Maps error no. to error string by GrandFather (Saint) on Aug 17, 2006 at 04:18 UTC
I suspect that is internal magic and you are not supposed to know. Very likely it is OS, or even build, specific. I only get 43 valid error strings using your test code. The rest are flagged as "Unknown error". (AS Perl version 5.8.7) DWIM is Perl's answer to Gödel	[reply]
Re: How Perl Maps error no. to error string by jesuashok (Curate) on Aug 17, 2006 at 04:28 UTC
Hi perl_lover The variables $@, $!, $^E, and $? are called as error indicators in perl. These variables also contain information about different types of error conditions that may appear during execution of a Perl program. The variables are shown ordered by the "distance" between the subsystem which reported the error and the Perl process. They corre- spond to errors detected by the Perl interpreter, C library, operating system, or an external program, respectively. $! is set to the C library's "errno" which inturn mapped to error string in perl compiler. For more information on this indicators refer perlvar "Keep pouring your ideas"	[reply]
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