stat() get group name is root
- by mengmenger
I have a file src.tar.gz whoes owner and group are named "src".
When I run test.c compiled with name "test" (permission: -rwsr-xr-x owner:root group:staff)
The way I run it:
I am running it as group member under "src" group.
But I run "test" as root since "test" permission is -rwsr-xr-x
Question:
Why did result come out like this? is the src.tar.gz group should be "src"?
Output:
Error: my group: src
Error: src.tar.gz group is root
test.c
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <grp.h>
void main(int ac, char **args) {
const char *ERR_MSG_FORMAT = "%s: %s %s.\n";
char *ptr_source_file = "src.tar.gz";
struct stat src_stat;
gid_t src_gid, my_gid;
int i = stat(ptr_source_file, &src_stat);
my_gid = getgid();
struct group *cur_gr = getgrgid(my_gid);
fprintf(stderr, ERR_MSG_FORMAT, "Error", "my group: ", cur_gr->gr_name);
src_gid = src_stat.st_gid;
struct group *src_gr = getgrgid(src_gid);
fprintf(stderr, ERR_MSG_FORMAT, "Error","src.tar.gz group is ", src_gr->gr_name);
}