Path: utzoo!dciem!nrcaer!scs!spl1!laidbak!att!pacbell!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!decwrl!sun!pitstop!sundc!seismo!uunet!mcvax!ukc!eag
From: lmjm@doc.ic.ac.uk (Lee McLoughlin)
Newsgroups: comp.os.minix
Subject: fix to libupack for pipes
Message-ID: <307@gould.doc.ic.ac.uk>
Date: 1 Jun 88 14:55:13 GMT
Article-I.D.: gould.307
References: <2584@louie.udel.EDU>
Reply-To: lmjm@doc.ic.ac.uk
Organization: Dept. of Computing, Imperial College, London, UK.
Lines: 32

In reply to the problems with lorder.  I found that it was going wrong
because libupack was trying to send it too much data down a pipe. Any more
than 7K and the write will fail.  Libupack also ignores failed writes - I
did not fix this.

Most programs are not effected by the write-to-pipe limit
because they use stdio which doesn't belt out so much data in one chunk.

Here is the necessary fix.  Basically it ouputs in 7K chunks.

0a1,3
> /* Limit on bytes that can be writen to a pipe */
> #define OUTMAX (7*1024)
> 
130a134
>   char *o;
137c141,145
< 	n = write(1, output, count);
---
> 	for( o = output; count > 0; o += OUTMAX ){
> 		int out = (count > OUTMAX) ? OUTMAX : count;
> 		n = write(1, o, out);
> 		count -= out;
> 	}

--
UKUUCP SUPPORT  Lee McLoughlin
	"What you once thought was only a nightmare is now a reality!"

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