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X-Authentication-Warning: localhost.localdomain: ronald owned process doing -bs
Date: Thu, 26 Jun 2003 12:03:17 +0200 (CEST)
From: Ronald Landheer-Cieslak <ronald AT landheer DOT com>
X-X-Sender: ronald AT localhost DOT localdomain
To: Vikram Mehta <vm6580 AT hotmail DOT com>
cc: "Cygwin AT Cygwin DOT Com" <cygwin AT cygwin DOT com>
Subject: Re: _pread() _pwrite
In-Reply-To: <Law14-OE48xJ6Zy1k4g00052fb6@hotmail.com>
Message-ID: <Pine.LNX.4.44.0306261146310.2545-100000@localhost.localdomain>
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pread and pwrite are not in Cygwin (or at least are not exported by 
cygwin1.dll). They are hardly the most portable functions in the world. I 
suggest you write a wrapper. Something like:

<UNTESTED CODE>
ssize_t pread(int fd, void *buf, size_t count, off_t offset)
{
	if (lseek(fd, offset, SEEK_SET) == (off_t)-1)
	{
		return(-1);
	}
	return(read(fd, buf, count));
}

and
ssize_t pwrite(int fd, const void *buf, size_t count, off_t offset)
{
	if (lseek(fd, offset, SEEK_SET) == (off_t)-1)
	{
		return(-1);
	}
	return(write(fd, buf, count));
}
</UNTESTED CODE>

HTH

rlc

NB: you should of course have configure test for the presence of these 
functions and act accordlingly.. 

On Wed, 25 Jun 2003, Vikram Mehta wrote:

> Hi folks,
> I am compiling some files which need functions like -pread(), pwrite() which
> shud be in libc.a.
> But they are not.
> 
> This file was actually mean to be complied on linux.
> 
> 
> Any ideas how can I overcome this problem
> 
> Vikram
> 
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