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Hi there!
i'm using redhat 7.1 (kernel 2.4.2-2)
I
was binding 4scsi disks to /dev/raw/raw1 ~ /dev/raw/raw4.
Here is the
query about raw :
[root@cetus codes]# raw
-qa
/dev/raw/raw1: bound to major 8, minor 1
/dev/raw/raw2:
bound to major 8, minor 2
/dev/raw/raw3: bound to major 8, minor
3
/dev/raw/raw4: bound to major 8, minor 4
then i make a
sample code like below :
#include
<stdio.h>
#include <stdlib.h>
#include
<string.h>
#include <sys/stat.h>
#include
<sys/types.h>
#include <fcntl.h>
#include
<unistd.h>
#include <errno.h>
int
main()
{
const char* path = "/dev/raw/raw1"
;
char *buf ;
struct stat f_stat
;
int fd ;
int len
;
if((fd = open(path, O_RDWR, 0)) < 0)
{
printf("Can't open file : %s\n",
path) ;
exit(0)
;
}
printf("FD is %d\n", fd)
;
stat(path, &f_stat) ;
printf("File size = %d\n", f_stat.st_size) ;
buf =
(char*) malloc(512) ;
memset(buf, 'a', 512)
;
lseek(fd, 0, SEEK_SET) ;
len =
write(fd, buf, 512) ;
if(len < 0)
{
printf("Can't Write...!!\n")
;
printf("Error No => %s\n",
strerror(errno)) ;
exit(0)
;
}
printf("Write %d bytes\n",
len) ;
return 0 ;
}
but the result
is
[root@cetus codes]# ./ex01
FD is 3
File size
= 0
Can't Write...!!
Error No => Invalid argument
Why
...?
Of cource i had read FAQ but i couldn't understand that.
Can
you explain more detail..?
Thank for your help.....^^
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