To write a C program using open, read, write, close , create , fork() system calls.

1.Star the program.

2.Open a file for O_RDWR for R/W,O_CREATE for creating a file ,O_TRUNC for truncate

a file.

3.Using getchar(), read the character and stored in the string[] array.

4.The string [] array is write into a file close it.

5.Then the first is opened for read only mode and read the characters and displayed it and

close the file.

6.Use Fork().

7.Stop the program.

#include<sys/stat.h>
#include<stdio.h>
#include<fcntl.h>
#include<sys/types.h>
int main()
{
int n,i=0;
int f1,f2;
char c,strin[100];
f1=open("data",O_RDWR|O_CREAT|O_TRUNC);
while((c=getchar())!='\n')
{
strin[i++]=c;
}
strin[i]='\0';
write(f1,strin,i);
close(f1);
f2=open("data",O_RDONLY);
read(f2,strin,0);
printf("\n%s\n",strin);
close(f2);
fork();
return 0;
}

Thus, open, read, write, close , create , fork() system calls implemented successfully using C program.