Re: readpipe patch again

[Akim Demaille]

| Using `fork' will be deadly for dos/windows. Please try to avoid it
| if possible.  I would like to suggest two alternatives at least for
| dos/djgpp:
| 
| - the use of popen/pclose.
| - the use of posix_spawn* family of functions.
| 
| Information about posix_spawn* family of functions are available
| from http://www.opengroup.org/
| 
| Both alternatives are available for DJGPP and would make
| the bison code be compilable out-of-the-box.

My reading of the situation is that we will welcome patch to implement
alternative means to invoke M4.  But I concur with Paul: fighting for
portability to poor systems is really a nightmare that anyway is best
solved by its users.  We will leave this task to the DOS user.