From: khan AT xraylith DOT wisc DOT edu (Mumit Khan)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: -frepo flag, is it supported?
Date: 18 Oct 1998 07:01:58 GMT
Organization: Center for X-ray Lithography, UW-Madison
Lines: 38
Message-ID: <70c3p6$1r02$1@news.doit.wisc.edu>
References: <000b01bdf929$2688b230$6dd22b0f AT ros51675cra DOT rose DOT hp DOT com>
NNTP-Posting-Host: modi.xraylith.wisc.edu
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

In article <000b01bdf929$2688b230$6dd22b0f AT ros51675cra DOT rose DOT hp DOT com>,
Andrew Crabtree <djgpp AT delorie DOT com> wrote:
>
>
>G.J. de Vries <gerjon AT euronet DOT nl> wrote in message
><1 DOT 5 DOT 4 DOT 32 DOT 19981016122919 DOT 0066bf88 AT mail DOT euronet DOT nl>...
>> Hi,
>>
>> I have a single question about DJGPP: does it support the -frepo flag.
>I don't think it works correctly without collect2.  I made a couple of goes
>at porting collect2 over but never got it working properly.  Collect2 relies
>heavily on fork, and the djgpp fork does not work (mainly because does
>doesn't multitask).
>

Actually, the fork() is used to simply redirect the child program's (ld, nm
etc) stdout and stderr, so it should be pretty easy to make collect2 work
under djgpp. I remember doing this for mingw32, and it was quite simple.
Unfortunately, it was quite messy for mingw32 and I decided to retract my
patch to discourage folks from using it (you should never need to use
-frepo hack at least on ELF and PE-COFF). 

There are two ways:
  
  - use a temporary file. Write a popen like replacement that redirects
    both stdout and stderr. I believe the djgpp's popen already uses temp
    files, so it's already there in source form to reuse. Modify 
    collect_execute (or is it fork_execute?) to do the right thing.
 
  - dup/save the parent's stdout/err, spawn the child with the new
    descriptors for stdout/err, restore parent's stdout/err and read
    from the child's stdout/err. This is what I did for mingw32 if I
    remember correctly. It should be somewhere on egcs mailing lists
    (before the lists were split).

Regards,
Mumit