in reply to Using FLY to print to STDOUT

Take a peek at IPC::Open2. It lets you write to a program via STDIN and read from the same program via STDOUT. I've used it with great success.

-- vek --

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Re: Re: Using FLY to print to STDOUT
by chrono86 (Novice) on Oct 05, 2002 at 02:25 UTC
    I tried it using the open2 function, but for some reason the readhandle is empty. maybe i'm using it wrong, since the readhandle is empty perl hangs when i try to read from it. 
    #!D:\perl\bin\

use IPC::Open2;

$flyprog = "d:\\perl\\fly\\fly.exe";

open2 (*BOY, *FLY, "$flyprog -q");

print FLY "new\n";
print FLY "size 256,256\n";
print FLY "fill 1,1,255,255,255\n";
print FLY "arc 128,128,180,180,0,360,0,0,0\n";
print FLY "fill 128,128,255,255,0\n";
print FLY "arc 128,128,120,120,0,180,0,0,0\n";
print FLY "arc 96,96,10,10,0,360,0,0,0\n";
print FLY "arc 160,96,10,10,0,360,0,0,0\n";
print FLY "fill 96,96,0,0,0\n";
print FLY "fill 160,96,0,0,0\n";
print FLY "string 0,0,0,10,240,giant,Hello, World!\n";
print FLY "string 0,0,0,100,10,medium,Don't worry, be Happy!\n";
close(FLY);

$output = <BOY>;
close(BOY);

print "Content-type: image/gif\n\n";
binmode(STDOUT);
print $output;

    [download]
    It SHOULD work, but it doesn't for some reason. I must be doing something wrong.
[reply]
[d/l]
      Make sure you use warnings and strict. Make sure you check to see if the call to open2 failed. 
      open2 (*BOY, *FLY, "$flyprog -q") || die "open2 $flyprog - $!\n';

      [download]
      Does fly.exe stream the data back to you via STDOUT? If so you might want to loop over the STDOUT filehandle: 
      while (<BOY>) {
   $output .= $_;
}
close (BOY);

      [download]
      -- vek --
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