C4-2 THE USAGE OF ACCESS

#include "apue.h"
#include <fcntl.h>

int main(int argc,char * argv[])
{
    if  ( argc != 2)
        err_quit("usage: a.out  ");

    if ( access(argv[1],R_OK) < 0)
        err_ret(" access error for %s",argv[1]);
    else
        printf("read access ok \n");


    if ( open(argv[1],O_RDONLY) < 0)
        err_ret("open error for %s",argv[1]);
    else
        printf(" open for reading ok\n");
    exit(0);

}

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