Question

Write a simple grep like simple utility in the C programming language. Approach the problem by following these steps: a) Your task is to write a simple grep like utility in the C programming language. You can name it “mygrep”. grep is basically used for searching. For example, “mygrep foo myfile” command returns all the lines that contain a string matching the expression "foo" in the file. Your code will be checked by running such a simple command. It is easy to get overwhelmed with the complexity of grep. Note that we are looking for a simple version that can search for a specific string in a single file. You may consult grep man page if you are looking to get more info about it.

USE SYSTEM CALLS:

i) open ii) read iii) write iv) close

Answer 1

#include<stdio.h>
#include<string.h>
void main()
{
char filename[20],pattern[20],t[250];
FILE *p;
printf("Enter file name\n");
scanf("%s",filename);
printf("Enter pattern to be searched\n");
scanf("%s",pattern);
p=fopen(filename,"r");
while(!feof(p))
{                                         
fgets(t,1000,p);
if(strstr(t,pat))
  printf("%s",t);                                  

}
fclose(p);
}