Ken Lehman wrote:
> I want to be able to return a true or false value from a function in a
> module and populate the $! variable with the specific errors. Is this
> possible? Is there documentation on how to do this? I can find docs on how
> to use $! but not how to set it. Thanks for any help
$! is tied to errno which is basically (usually) an interger set by the
system calls in case of an error. it's defined by the ISO C standard. you
can't set errno to an arbitrary number or string and expect the it to work.
check 'man errno' for a full discussion. you can check your system's errno.h
to see values are defined for errno. for example, in my linux box:
[panda]# more /usr/include/asm/errno.h
...
#define ENOTBLK 15 /* Block device required */
#define EBUSY 16 /* Device or resource busy */
#define EEXIST 17 /* File exists */
...
you can then assign $! like:
[panda]# perl -MErrno=:POSIX -le '$!=ENOTDIR; print $!+0,": ",$!'
20: Not a directory
mess with errno only when you really need to!
david
--
sub'_{print"@_ ";* \ = * __ ,\ & \}
sub'__{print"@_ ";* \ = * ___ ,\ & \}
sub'___{print"@_ ";* \ = * ____ ,\ & \}
sub'____{print"@_,\n"}&{_+Just}(another)->(Perl)->(Hacker)
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