Re^2: Can't spawn "cmd.exe":

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Re^3: Can't spawn "cmd.exe": by ikegami (Patriarch) on Mar 18, 2009 at 15:32 UTC
in windows what would be the "normal" return code, 0 or 1? 0 for success, like unix. then did echo %ERRORLEVEL% and the value returned was -1. That's weird. Error codes are unsigned in Win32. `IF ERRORLEVEL` even relies on that. `@echo off program.exe if errorlevel 3 goto ERROR if errorlevel 1 goto WARNING rem 0 <= errorlevel < 1 echo Success goto END :WARNING rem 1 <= errorlevel < 3 echo Warning goto END :ERROR rem 3 <= errorlevel echo Error :END` [download] That's a very strange error message to return in the event of a negative return code. No, the message is correct for a negative code being returned from the function that implements `system`. The problem is that the function is returning negative when the child was successfully launched. In Win32, exit codes are unsigned 32 bit values. Perl treats it as a signed 32-bit value. `DWORD status; ... GetExitCodeProcess(ProcessInformation.hProcess, &status); ret = (int)status;` [download] The second line is a bug. Sufficiently high exit codes will be converted to negative. Negatives are used to signal a problem launching the process.	[reply] [d/l] [select]
Re^4: Can't spawn "cmd.exe": by BrowserUk (Patriarch) on Mar 19, 2009 at 14:16 UTC
And most of that guff is wrong also. Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. "Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."	[reply]
Re^3: Can't spawn "cmd.exe": by runrig (Abbot) on Mar 18, 2009 at 15:23 UTC
"Normal" return code seems to be zero. E.g., do a "dir" and then echo %ERRORLEVEL%. Now do "dir file_that_doesnt_exist" and echo %ERRORLEVEL% again. Now do " `perl -e exit(-1)`".	[reply] [d/l]
Re^3: Can't spawn "cmd.exe": by almut (Canon) on Mar 18, 2009 at 15:51 UTC
echo %ERRORLEVEL% ... Is this the proper way to check this? Yes, I think so, but I'm no Windows expert... As to the negative return code, IIRC, I was able to reproduce the issue last time with a self-compiled perl-5.8.8 on a Win XP (32-bit) vmware image. Unfortunately, I don't have access to that image at the moment, and any attempts to reproduce the problem on the Windows box I currently have access to (XP x64 SP2, with ActiveState's Perl 5.8.8) have failed so far... Maybe I'll continue to play with this later. In case I should dig up something of interest, I'll report back.	[reply]