Hello,
Using O_DIRECT flag, read() failed and errno is EINVAL.
kernel 2.4.22
Filesystem Ext3 mount on /home
What's wrong ?
Thanks
Yves Crespin
#gcc -Wall -D_GNU_SOURCE direct.c -o direct
#cp direct d
#./direct d
#open failed [d] 040402 0666 errno 22
#
/* --- start code --- */
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#define O_BINARY 0
int main(int argc,char *argv[])
{
struct stat sbuf;
char buf[8192];
int openFlags;
int fd;
int nb;
int size;
if (argc!=2){
printf("Missing file name\n");
exit(2);
}
openFlags = O_RDWR|O_BINARY|O_NOCTTY;
openFlags |= O_DIRECT; /* Not POSIX */
fd = open(argv[1],openFlags,0666);
if (fd==-1){
printf("open failed [%s] %#o %#o errno
%d\n",argv[1],openFlags,0666,errno);
exit(1);
}
if (fstat(fd,&sbuf)<0){
printf("fstat failed\n");
exit(1);
}
size = sbuf.st_blksize;
if (size > sizeof(buf)){
printf("Page size too big\n");
exit(3);
}
if (size > sbuf.st_size){
printf("File too small\n");
exit(3);
}
nb = read(fd,buf,size);
if (nb != size){
printf("read failed fd %d size %d nb %d errno
%d\n",fd,size,nb,errno);
exit(1);
}
if (close(fd)){
printf("close failed\n");
exit(1);
}
return 0;
}
/* --- end code --- */
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
