Unix Prog: Files -- Directories(1)

1. mkdir
mkdir system call can be used to create new directory

definition:

 ubuntu@ip-172-31-23-227:~$ less /usr/include/unistd.h  
 ......  
 /* Remove the directory PATH. */  
 extern int rmdir (const char *__path) __THROW __nonnull ((1));  
 ......  
 ubuntu@ip-172-31-23-227:~$ less /usr/include/x86_64-linux-gnu/sys/stat.h  
 ......  
 /* Create a new directory named PATH, with permission bits MODE. */  
 extern int mkdir (const char *__path, __mode_t __mode)  
    __THROW __nonnull ((1));  
 ......  

fileio.c:

 #include<stdio.h>  
 #include<stdlib.h>  
 #include<sys/stat.h>  
 #include<unistd.h>  
   
 int main(int argc, char* argv[])  
 {  
  if(mkdir(argv[1], S_IRWXU) < 0) {  
   printf("mkdir error!\n");  
   exit(1);  
  }  
   
  exit(0);  
 }  

shell:
1）Create the new directory with rwx------ permission.
2) List all files

 ubuntu@ip-172-31-23-227:~$ ./makedir.out testdir  
 ubuntu@ip-172-31-23-227:~$ ls -lrt  
 total 24  
 -rw-rw-r-- 1 ubuntu ubuntu 202 Aug 24 20:28 fileio.c~  
 -rw-rw-r-- 1 ubuntu ubuntu 210 Aug 24 20:30 fileio.c  
 -rwxrwxr-x 1 ubuntu ubuntu 9717 Aug 24 20:30 makedir.out  
 drwx------ 2 ubuntu ubuntu 4096 Aug 24 20:30 testdir  

2. rmdir
rmdir system call can be used to remove directory

definition: same as above

fileio.c:

 #include<stdio.h>  
 #include<stdlib.h>  
 #include<sys/stat.h>  
 #include<unistd.h>  
   
 int main(int argc, char* argv[])  
 {  
  if(rmdir(argv[1]) < 0) {  
   printf("mkdir error!\n");  
   exit(1);  
  }  
   
  exit(0);  
 }  

shell:

 ubuntu@ip-172-31-23-227:~$ ./removedir.out testdir  
 ubuntu@ip-172-31-23-227:~$ ls -lrt testdir  
 ls: cannot access testdir: No such file or directory