[Bug 22138] New: system(NULL) generates SIGSEGV

http://bugs.winehq.org/show_bug.cgi?id=22138

Summary: system(NULL) generates SIGSEGV
           Product: Wine
           Version: 1.1.41
          Platform: x86
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: msvcrt
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

When an application calls system(NULL) or _wsystem(NULL), a SIGSEGV is
generated.
Actually the code of _wsystem() does not check the value of cmd parameter as
described here:

Perhaps a better implementation would be something like to:

comspec = msvcrt_get_comspec();
if (cmd == NULL)
    return (comspec == NULL) ? 0 : 1;
else
if (comspec == NULL)
    return -1;