LINUX PROGRAMMING
MINI PROJECT
ON

PROJECT TO SIMULATE THE BEHAVIOUR OF MOVE COMMAND AND DEVELOP A NEW COMMAND THAT DOES THE WORK.

SUBMITTED BY: SHOBHIT MATHEW (RK2102B22) (11104723)

ACKNOWLEDGEMENT
We got help from many people during the course of this project. We would specially like to thank our Linux programming teacher Ms. Sheena Singh who helped us to complete this project. We would like to thank some of our colleagues who helped us to complete this project. Without their help and support it would not be possible for us to complete this project.

CONTENTS TOPICS
INTRODUCTION System Calls Command line Argument Program Bibliography

PAGE NO.
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INTRODUCTION
In this program various operations are performed using move command like moving half of the content from one file to another, move the complete information from one file to another, append the file using move command etc. by using system call in linux.

MOVE COMMAND
This command will move the content of one file to another and delete the first file.

SYSTEM CALLS
Various system calls used are:• OPEN system call:- it will help in opening a new file. Syntax:- fd=open(“const-char-pathname”, flag, mode); • READ system call:- to read the contents from a file. Syntax:- read(fd, buff, size_count); • WRITE system call:- it is used to write some content into the file. Syntax:- write fd,&buffer address,size_count);

• LSEEK system call:- to move the curser in the file Syntax:- lseek(fd, offset, whence); • REMOVE system call:- to delete a particular file Syntax:- rm(“filename”);

COMMAND LINE ARGUMENT
The arguments which are passed during the run time are called command line arguments. In this GETOPT function is used. Inside main we are using it as: • Int main(int argc, char *argv[]) • Syntax:- int getopt(int argc, char *argv[], const char *optstring); extern char *optarg; extern int optind, opterr, optopt; • If the option takes a value that value is pointed by the external variable optarg. • Getopt returns -1 when there are no more options to process. • Getopt returns ? if there is an unrecognized option,which it stores in external variable optopt. • The external variable optind is set to the index of the next argument to process.

PROGRAMMING
#include #include #include #include #include #include #include #include int main() { int option,fd,n,x,fd2,m,y; char buff[1000]; printf("press 1 to move half of the content of file \n"); printf("press 2 to move complete content from 1 file 2 another \n"); printf("press 3 to append the file \n"); scanf("%d",&option); switch(option) { case 1: {

fd=open("f11.txt",O_CREAT|O_RDWR); //creat a new file in //read write mode n=write(fd,"hi this is pratik",17); //write into the file n=read(fd,"hi this is pratik",17); printf("content of first file is \n"); write(1,"hi this is pratik",17); x=lseek(fd,-12,SEEK_END); //move the curser into the file fd2=open("f12.txt",O_CREAT|O_RDWR); m=write(fd2,"hi this is pratik",x); printf("\ncontent of 2nd file is \n"); write(1,"hi this is pratik",7); close(fd); close(fd2); break; }

case 2: {

fd=open("f11.txt",O_CREAT|O_RDWR); //creat a new file in //read write mode n=write(fd,"hi this is pratik",17); //write into the file n=read(fd,"hi this is pratik",17); printf("content of first file is \n"); write(1,"hi this is pratik",17); x=lseek(fd,-17,SEEK_END); //move the curser into the file

fd2=open("f12.txt",O_CREAT|O_RDWR); m=write(fd2,"hi this is pratik",x); printf("\ncontent of 2nd file is \n"); write(1,"hi this is pratik",17);

remove("f11.txt"); //delete the first file printf("\n file one is deleted \n"); printf("the content of file one is \n"); write(1,buff,n); close(fd);

close(fd2); break; } case 3: {

fd=open("f11.txt",O_CREAT|O_RDWR); //creat a new file in //read write mode n=write(fd,"hi this is pratik",17); //write into the file n=read(fd,"hi this is pratik",17); printf("content of first file is \n"); write(1,"hi this is pratik",17); x=lseek(fd,-17,SEEK_END); //move the curser into the file fd2=open("f12.txt",O_CREAT|O_RDWR); m=write(fd2,"hi this is pratik",x);

printf("\ncontent of 2nd file is \n"); write(1,"hi this is pratik",17); remove("f11.txt"); //delete the first file printf("the content of file one is \n"); write(1,buff,n); printf("\n file one is deleted \n"); lseek(fd2,17,SEEK_SET); y=write(fd2,"this is the new content",23); printf("new content of 2nd file is\n"); write(1,"hi this is pratik",17); write(1," this is the new content\n",24);

close(fd); close(fd2); break; }

}

return 0; }

BIBLIOGRAPHY
• Beginning linux programming • www.1000projects.com • www.slideworld.com • www.wikipedia.org