[configure.ac/uClinux] Adding code for fork/vfork?

[Gilles]

Hello,

A cross-compile toolchain that I use just refuses to compile any code
that uses fork() because uClinux uses vfork() instead:

"undefined reference to `_fork'"

However, some applications use if/else blocks just as this one instead
of eg. "#ifdef HAVE_FOR" conditional compiling:
============
if (uClinux) {
        *pid = vfork();
} else {
        *pid = fork();
}
============

Is it possible to modify configure.ac so that it goes ahead and
compiles applications that handle fork/vfork without preprocessor
commands?

Thank you.