TYBcs OS-Syspro Slip 13-2 | IProgramX

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

void make_toks(char *s, char *tok[])
{
int i=0;
char *p;

p = strtok(s," ");
while(p!=NULL)
{
tok[i++]=p;
p=strtok(NULL," ");
}

tok[i]=NULL;
}

void search(char *fn, char op, char *pattern)
{
int fh,count=0,i=0,j=0;
char buff[255],c,*p;

fh = open(fn,O_RDONLY);
if(fh==-1)
{
printf("File %s Not Found\n",fn);
return;
}

switch(op)
{
case 'f':
while(read(fh,&c,1))
{
buff[j++]=c;
if(c=='\n')
{
buff[j]='\0';
j=0;
i++;
if(strstr(buff,pattern))
{
printf("%d: %s",i,buff);
break;
}
}
}
break;
case 'c':
while(read(fh,&c,1))
{
buff[j++]=c;
if(c=='\n')
{
buff[j]='\0';
j=0;
p = buff;
while(p=strstr(p,pattern))
{
count++;
p++;
}
}
}
printf("Total No.of Occurrences = %d\n",count);
break;
case 'a':
while(read(fh,&c,1))
{
buff[j++]=c;
if(c=='\n')
{
buff[j]='\0';
j = 0;
i++;
if(strstr(buff,pattern))
printf("%d: %s",i,buff);
}
}
}//switch
close(fh);
}//search

int main()
{
char buff[80],*args[10];
int pid;

while(1)
{
printf("myshell$");
fflush(stdin);
fgets(buff,80,stdin);
buff[strlen(buff)-1]='\0';
make_toks(buff,args);
if(strcmp(args[0],"search")==0)
search(args[3],args[1][0],args[2]);
else
{
pid = fork();
if(pid>0)
wait();
else
{
if(execvp(args[0],args)==-1)
printf("Bad command.\n");
}
}
}

return 0;
}