largefiletest.cpp

qt-x11-opensource-src-4.1.4.tar.gz源码

/* Sample program for configure to test Large File support on target
platforms.
*/

#define _LARGEFILE_SOURCE
#define _LARGE_FILES
#define _FILE_OFFSET_BITS 64
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <assert.h>
#include <stdio.h>

int main( int, char **argv )
{
// check that off_t can hold 2^63 - 1 and perform basic operations...
#define OFF_T_64 (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
    if (OFF_T_64 % 2147483647 != 1)
	return 1;

    // stat breaks on SCO OpenServer
    struct stat buf;
    stat( argv[0], &buf );
    if (!S_ISREG(buf.st_mode))
	return 2;

    FILE *file = fopen( argv[0], "r" );
    off_t offset = ftello( file );
    fseek( file, offset, SEEK_CUR );
    fclose( file );
    return 0;
}