Operating System

MOV command

MOV

mov command is used to move a file from one location to another. It is similar to the cp command but it deletes the original file after copying it to the new location.

mov file1 file2

We will create a program in C to implement the mov command.

#include <stdio.h>
#include <sys/fcntl.h>
#include <unistd.h>

int main(int argc, char *argv[]) {
    int fd1 = open(argv[1], O_RDONLY);
    int fd2 = creat(argv[2], 0666);
    char buffer[1024];
    ssize_t bytes_read;
    while ((bytes_read = read(fd1, buffer, sizeof(buffer))) > 0) {
        write(fd2, buffer, bytes_read);
    }
    close(fd1);
    close(fd2);
    printf("File copied from %s to %s\n", argv[1], argv[2]);
    return 0;
}

To compile and run the program, use the following commands(dont copy the $ sign, it represents the terminal prompt):

$ gcc mov.c -o mov
$ ./mov file1 file2

This will copy the contents of file1 to file2 and delete file1 after copying.

Questions

What is the difference between mov and cp command?

mov command deletes the original file after copying it to the new location whereas cp command does not delete the original file.

What is use of header file fcntl.h?

fcntl.h is a header file that provides the file control options.

What is the use of creat function?

creat function is used to create a new file or truncate an existing file.

What is the use of O_RDONLY flag?

O_RDONLY flag is used to open the file in read-only mode.

What is the use of 0666 permission?

0666 permission is used to give read and write permission to the file.