could you help me get the program to loop back to asking for 2 strings and only

Question

could you help me get the program to loop back to asking for 2 strings and only ending if quit is input

#include <iostream>

#include <fstream>

#include <string.h>

#include <sys/types.h>

#include <sys/wait.h>

#include <unistd.h>

#include <stdlib.h>

using namespace std;

int main(int argc, char const *argv[])

{

int pfd[2];

pipe(pfd);

char op = 'y';

char cmdn1[10][20] = {0}; // saparate it

char cmdn2[10][20] = {0}; // saparate it

char * argv1[10] ; // give it to argv

char * argv2[10] ; // give it to argv

int i , j = 0 , k = 0;

char a[20]={0};

int wordc1 = 0;

int wordc2 = 0;

string quit;

while (quit[0] != 'Q' && quit[0] != 'q')

{

string string1, string2;

cout << "enter first string ";

getline(cin, string1);

cout << "enter second string ";

getline(cin, string2);

for( i =0 ; i<10;i++)

argv1[i] = NULL; // in the starting null all pointer

k = 0, j = 0 , i = 0;

for(i=0;i <= string1.size() ; i++)

{

if(string1[i] == ' ' || string1[i] == '') // saparate command

{

a[j] = '';   

strcpy(cmdn1[k++],a);

argv1[k-1] = cmdn1[k-1]; // allocate each saparate argument to argv

j = 0;

wordc1++;

memset(a,0,sizeof(a));

}

else

a[j++] = string1[i];

}

for( i =0 ; i<10;i++)

argv2[i] = NULL; // in the starting null all pointer

k = 0, j = 0 , i = 0;

for(i=0;i <= string2.size() ; i++)

{

if(string2[i] == ' ' || string2[i] == '') // saparate command

{

a[j] = '';   

strcpy(cmdn2[k++],a);

argv2[k-1] = cmdn2[k-1]; // allocate each saparate argument to argv

wordc2++;

j = 0;

memset(a,0,sizeof(a));

}

else

a[j++] = string2[i];

}

if (fork() == 0)

{

// child gets here and handles "grep Villanova"

// replace standard input with input part of pipe

dup2(pfd[0], 0);

// close unused hald of pipe

close(pfd[1]);

// execute grep

execvp(argv2[0], argv2);

}

else

{

// parent gets here and handles "cat scores"

// replace standard output with output part of pipe

dup2(pfd[1], 1);

// close unused unput half of pipe

close(pfd[0]);

// execute cat

execvp(argv1[0], argv1);

}

cin.clear();

cin.ignore(255,' ');

cout << "Do you want to quit (quit/no)? "; //this part not working .

cin >> quit;

}

}

Explanation / Answer

here is the code , i didn't look to your program i just did the loop

#include <iostream>
#include <fstream>
#include <string.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <stdlib.h>
using namespace std;
int main(int argc, char const *argv[])
{
int pfd[2];
pipe(pfd);
char op = 'y';
char cmdn1[10][20] = {0}; // saparate it
char cmdn2[10][20] = {0}; // saparate it
char * argv1[10] ; // give it to argv
char * argv2[10] ; // give it to argv
int i , j = 0 , k = 0;
char a[20]={0};
int wordc1 = 0;
int wordc2 = 0;
string quit;
do    // use do , this will execute atleast one time
{
string string1, string2;
cout << "enter first string ";
getline(cin, string1);
cout << "enter second string ";
getline(cin, string2);
for( i =0 ; i<10;i++)
argv1[i] = NULL; // in the starting null all pointer
k = 0, j = 0 , i = 0;
for(i=0;i <= string1.size() ; i++)
{
if(string1[i] == ' ' || string1[i] == '') // saparate command
{
a[j] = '';
strcpy(cmdn1[k++],a);
argv1[k-1] = cmdn1[k-1]; // allocate each saparate argument to argv
j = 0;
wordc1++;
memset(a,0,sizeof(a));
}
else
a[j++] = string1[i];
}
for( i =0 ; i<10;i++)
argv2[i] = NULL; // in the starting null all pointer
k = 0, j = 0 , i = 0;
for(i=0;i <= string2.size() ; i++)
{
if(string2[i] == ' ' || string2[i] == '') // saparate command
{
a[j] = '';
strcpy(cmdn2[k++],a);
argv2[k-1] = cmdn2[k-1]; // allocate each saparate argument to argv
wordc2++;
j = 0;
memset(a,0,sizeof(a));
}
else
a[j++] = string2[i];
}
if (fork() == 0)
{
// child gets here and handles "grep Villanova"
// replace standard input with input part of pipe
dup2(pfd[0], 0);
// close unused hald of pipe
close(pfd[1]);
// execute grep
execvp(argv2[0], argv2);
}
else
{
// parent gets here and handles "cat scores"
// replace standard output with output part of pipe
dup2(pfd[1], 1);
// close unused unput half of pipe
close(pfd[0]);
// execute cat
execvp(argv1[0], argv1);
}
cin.clear();
cin.ignore(255,' ');
cout << "Do you want to quit (quit/no)? "; //this part not working .
cin >> quit;
}while(quit !="quit"); // in this manner we loop the program like declar char ch; at begining cout<<"continue(y/n)"; cin>>ch; }while(ch =='y' || ch == 'Y');
}

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.