You are Suffering from Buffering. When you swap your output to file writes, the buffering behavior is swapped as well. You can repair this by making STDIO "hot" by setting the special variable $| to true. The following code behaves as you would expect.

## try.pl ##
use strict;
use warnings;
#use Inline C => Config => BUILD_NOISY => 1;

use Inline C => <<'END_C';

void foo(int i) {
        printf("From C: %d\n", i);
        /* Flush all IO buffers */
        fflush(NULL);
}


END_C

$| = 1;
for (my $i =0; $i < 10; ++$i) {
        print "From perl: $i\n";
        foo(++$i);
}

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P.S. You didn't get bit this time, but you should always use strict;. Perhaps that was a transcription error, given that you use warnings;.

In reply to Re: Buffered, bruised and broken by kennethk
in thread Buffered, bruised and broken by syphilis

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