how to detect when compiler emits an error

To compile a C++ project, I want to write a perl script to compile my program and see if the compilation went wrong or not. If the compiler gives any compilation erro开发者_C百科r, I'll need to perform some other task.

The perl script will be something like this:

   @l1 =  `find . -name '*.c'`;
   @l2 =  `find . -name '*.cpp'`;
   @l3 =  `find . -name '*.cc'`;
   my $err;
   my $FLAGS = "-DNDEBUG"   
   push(@l , @l1, @l2, @l3);
   chomp(@l);
   foreach (@l) {
     print "processing file $_ ...";
     $err = `g++ $_ $FLAGS`;
     if($err == something) {
       #do the needful
     }
   }

so what should be something?

You should check $? instead, after g++....

perlvar

$?

The status returned by the last pipe close, backtick (`` ) command, successful call to wait() or waitpid(), or from the system() operator.

The exit value of the subprocess is really ($?>> 8)

So you should check if g++ returned 0 (success) or non-zero.

if ($? >> 8) {
    /* Error? */
}

IPC::System::Simple/IPC::Run3 make this easier