Write a c program to know read/write permission of given file.

#include "time.h"
#include "sys\stat.h"
#include "stdio.h"
void main(){
    struct stat status;
    FILE *fp;
    if (status.st_mode & S_IREAD)
         printf("You have read permission.\n");
    if (status.st_mode & S_IWRITE)
         printf("You have write permission.");


Function  int stat(char *, struct stat *) store the  information of open file in form of  structure struct stat

Structure struct stat has been defined in sys\stat.h as
struct stat {
    short  st_dev,   st_ino;
    short  st_mode,  st_nlink;
    int    st_uid,   st_gid;
    short  st_rdev;
    long   st_size,  st_atime;
    long   st_mtime, st_ctime;

(i)st_dev: It describe file has stored in which drive of your computer.

(j)st_mode:  It describe various mode of file like file is read  only, write only, folder, character file etc.

(k)st_size: It tells the size of file in byte.

(l)St_ctime:It tells last data of modification of the file.

There are some macro has been defined in sys\stat.h

 Name          Meaning
 S_IFMT       File type mask
 S_IFDIR      Directory
 S_IFIFO      FIFO special
 S_IFCHR      Character special
 S_IFBLK      Block special
 S_IFREG      Regular file
 S_IREAD      Owner can read
 S_IWRITE     Owner can write
 S_IEXEC      Owner can execute

So masking or bit wise and operation between status.st_mode and S_IREAD return true you have read permission and so on 

2.  Write a c program to delete a file.
3. Write a c program to copy a file from one location to other location.
6. Write a c program which writes string in the file.

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