From: Nate Eldredge <neldredge AT hmc DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: DJGPP: setvbuf()
Date: 30 May 2000 20:42:52 -0700
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RadSurfer <Radsmail AT juno DOT com> writes:

> Can anyone please provide any additional information
> about   setvbuf()   ?
> 
> I've used this and it does appear to work.
> But the files MUST BE LARGE before and significant savings
> in processor time is noticed....
> 
> My Question is:
> How is   setvbuf   done?
> Is this an Interrupt Call of some kind ? such as available
> thru  DOS or BIOS calls?

No.  All it really does is tweak some flags in the FILE struct so that
the stdio functions (printf, fread, etc) know how much buffering to do.

> I've been too lazy to try to dig up the specific LIBC
> source file that might shed some light on this; BESIDES
> I'd appreciate any ADDITIONAL information as well as
> how its actually sourced....

id-utils are handy for this.

src/libc/ansi/stdio/setvbuf.c

-- 

Nate Eldredge
neldredge AT hmc DOT edu