Hi,

The C header file (mylib.h):

#include <stdio.h>

void my_puts(FILE*);
[download]

The C file (mylib.c):

#include <stdio.h>

void my_puts(FILE * stream) {
     fputs("hello from libmylib", stream);
}
[download]

Now, build the library (libmylib.a):

C:\_32\C>gcc -c mylib.c

C:\_32\C>ar cru libmylib.a mylib.o
[download]

The perl script that accesses the function in libmylib.a:

use warnings;
use strict;

use Inline C => Config =>
    INC => '-IC:/_32/C',
    LIBS => '-LC:/_32/C -lmylib',
    BUILD_NOISY => 1;

use Inline C => <<'EOC';
#include <mylib.h>
void foo(FILE * x) {
     my_puts(x);
     fflush(x);
}

EOC

$| = 1;

for(1 .. 2) {
   foo(*stdout);
   print "\nhello from perl\n";
}

for(1 .. 2) {
   foo(*stderr);
   print "\nhello from perl\n";
}
[download]

Ok ... so I've got this library (libmylib.a) that was built using mylib.h and mylib.c. For the purposes of this exercise, that (3rd party) library is to be considered non-modifiable. Of course, if it's doing something sinful, please let me know. And I've got an Inline::C script that's accessing the one and only function that's in libmylib.a

As it stands, the script outputs (on Win32, perl 5.8.8):

hello from libmylib
hello from perl
hello from libmylib
hello from perl
hello from libmylib
hello from perl
hello from libmylib
hello from perl
[download]

That's all well and good, and the exact output I'm wanting to see. But if I comment out the line that turns the autoflush on I get the following garbled output:

hello from libmylib
hello from perl
hello from libmylibhello from libmylibhello from libmylib
hello from perl

hello from perl

hello from perl
[download]

I simply do not see why the output should vary in any way, dependent upon whether autoflush is on or off. As I understand it, perl's autoflush will have no effect on the C buffers ... and, since the perl print() statements terminate with a "\n", autoflush should have no effect on the perl buffers either.

I guess I'm overlooking something ... but what ?

Cheers,
Rob

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