A9

Aim         :     Implement an assignment using File Handling System Calls (Low level system calls like open, read, write, etc)

#include<stdio.h>

#include<sys/types.h>

#include<sys/stat.h>

#include<stdlib.h>

#include<fcntl.h>

#include<string.h>

int main()

{

int fd, ch;

char fname[25];

char buffer[80];

ssize_t ret_in, ret_out;

char message[100];

do

{

printf("1.Create File\n");

printf("2.Write\n");

printf("3.Read\n");

printf("4.Exit\n");

printf("Enter your choice\t");

scanf("%d", &ch);

if(ch==1)

{

printf("Enter File Name\t");

scanf("%s",fname);

fd=creat(fname,S_IREAD| S_IWRITE);

if(fd==-1)

printf("Error in Opening file %s\n",fname);

else

{

printf("File %s is opened read/write access\n",fname);

printf("%s is currently empty\n",fname);

}

close(fd);

}

if(ch==2)

{

printf("Enter file name\t");

scanf("%s",fname);

fd=open(fname,O_WRONLY,1);

if(fd!=-1)

{

printf("file %s opened for write access\n",fname);

printf("Enter Data\t");

scanf("%s",message);

write(fd,message,sizeof(message));

close(fd);

}}

if(ch==3)

{

printf ("Enter file name\t");

scanf("%s",fname);

fd=open(fname,O_RDONLY,0);

if(fd!=-1)

{

printf("%s opened for read access\n",fname);

if(read(fd,buffer,sizeof(buffer)))

printf("\"%s\" was written to %s\n",buffer,fname);

else

printf("***Error reading %s **\n",fname);

}

close(fd);

}

}

while(ch!=4);

close(fd);

exit(0);

}

/*