bus error on using acl_get_fd , acl_set_fd

[rak1986]

Hi all,
I am trying to write a program to copy a file and also its ACL's. However, though the program compiles I get a bus error after acl_set_fd
Here is the program

#include<stdio.h>
#include<sys/types.h>
#include<errno.h>
#include<fcntl.h>
#include<sys/uio.h>
#include<unistd.h>
#include<sys/acl.h>

#define BUFSIZE 8192

int main(int argc,char *argv[])
{
        int fs , fd , ret ;
        acl_t acl = 0 ;
        char buffer[BUFSIZE];
        size_t nbytes = BUFSIZE ;
        ssize_t count ;
        if(argc == 3)
        {
                fs = open(argv[1],O_RDONLY) ;
                if(fs == -1)
                {
                        perror("cant open file for reading\n");
                        return 0 ;
                }
                fd = open(argv[2],O_RDWR | O_CREAT,0777);
                if(fd == -1)
                {
                        perror("cant open file for writing\n");
                        return 0;
                }
                acl = acl_get_fd(fs) ;
                if(acl = (acl_t)NULL)
                        perror("failed to get ACLs\n") ;
                while((count = read(fs , buffer , nbytes)))
                        write(fd , buffer , count) ;
                printf("File copy complete\n");
                printf("setting ACL's for file\n");
                ret = acl_set_fd(fd , acl) ;
                printf("Done!!!!!!");
                if(ret == -1)
                {
                        perror("Failed to set ACL\n");
                        return 0 ;
                }
                if(ret == 0)
                        printf("ACL set successfully\n");
                close(fd);
                close(fs);
        }
        else
                printf("usage : ./acl_prg source dest\n");
        return 0;
}

I am running this on Mac OS X 10.4

[rak1986]

This is the output I get :

# ./acl_prg 1.txt 2.txt
File copy complete
setting ACL's for file
Bus error

[Salem]

> if(acl = (acl_t)NULL)
You made it NULL, not tested it for NULL.

1. Casting NULL is unnecessary
2. Add more compiler warnings (say -Wall) to catch the problem early.
3. Use a debugger to trap the error, and allow you to examine the input parameters at the point of the fault.

[rak1986]

Oh, I completely overlooked that.

Thanks a lot for pointing out. Works fine now