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Mail Archives: cygwin/2006/03/21/23:06:12

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Date: Tue, 21 Mar 2006 20:05:59 -0800 (PST)
From: "Paul J. Lucas" <pauljlucas AT mac DOT com>
To: cygwin AT cygwin DOT com
Subject: Reading too few bytes
Message-ID: <Pine.LNX.4.63.0603212000250.23743@vgfl.cnhywyhpnf.bet>
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Here's a small test program:

	#include <fcntl.h>
	#include <cstdlib>
	#include <iostream>
	
	using namespace std;
	
	int main() {
	    int fd = ::open( "ESLF", O_RDONLY );
	    if ( fd == -1 ) {
	        cerr << "could not open ESLF file" << endl;
	        ::exit( 1 );
	    }
	    char buf[ 64 ];
	    ssize_t bytesRead = ::read( fd, buf, sizeof( buf ) );
	    cout << "read " << bytesRead << " bytes" << endl;
	    ::close( fd );
	}

Here's the contents of a small biinary file "ESLF" (printed in hex bytes):

	54 39 CA 1A 44

When I compile the program as:

	g++ -o test test.cpp

and run it, it prints "read 5 bytes" as one would expect.  When I compile
the program as:

	g++ -mno-cygwin -o test test.cpp

and run it, it prints "read 3 bytes".  Why?  How do I teg it to read all
5 bytes?

- Paul


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