Simulation Of UNIX Command - GREP

 #include<stdio.h>

#include<string.h>

int main(int argv,char *args[])

{

FILE *f;

char str[100];

char c;

char word[100];

int i,flag,j,m,k;

char ar[]="hi";

char temp[30];

if(argv<4)

{

printf("usage:  grep <pattern> <filename>\n\n");

return;

}

f=fopen(args[3],"r");

while(!feof(f))

{

i=0;

while(1)

{

fscanf(f,"%c",&c);

if(feof(f))

{

str[i++]='\0';

break;

}

if(c=='\n')

{

str[i++]='\0';

break;

}

str[i++]=c;

}

if(strlen(str)>=strlen(args[2]))

for(k=0;k<=strlen(str)-strlen(args[2]);k++)

{

for(m=0;m<strlen(args[2]);m++)

{

temp[m]=str[k+m];

}

temp[m]='\0';

if(strcmp(temp,args[2])==0)

printf("%s\n",str);

break;

}

}

return 0;

}

Output:

[telnet50@linux ~]$ ./a.out

usage:  grep <pattern> <filename>

[telnet50@linux ~]$ grep int grepdemo.c

int main(int argv,char *args[])

int i,flag,j,m,k;

printf("usage:  grep <pattern> <filename>\n\n");

printf("%s\n",str);