Core dump when writing to a file that has reached its maximum file size

[kgnu]

I have a file that's 2147483647 bytes long (2^31 -1).  Opening the file with
fopen  in append w/r mode is successful.  Attempting to write with fwrite() or
write() simply core dumps and prints 'File size limit exceeded (core dumped)'
to stderr.

I'm using RedHat 9 (Shrike) and glibc 2.3.2.

The man page says if it can't write to the file, it returns -1, yet it's not.

Regards,
Kurt