c++ - Why do spaces get lost in pipes in Linux? -

i have issue pipes in linux. looks space characters lost after piping. running following c++ code

#include <iostream> #include <stdio.h> #include <string.h>  using namespace std;  int main(){     char s[] = "ab cd", c;     int n = strlen(s);     for(int = 0; i<n && (cin >> c); i++)         if(s[i] != c){             printf("wrong @ %d : '%c' != '%c' \n", i, s[i], c);             break;         }     return 0; } 

from

echo "ab cd" | ./checker 

shell command gives

wrong @ 2 : ' ' != 'c' 

is normal behavior? how avoid losing characters in pipes?

the problem isn't pipe, problem cin >> c skips on whitespace.

it work if cin >> noskipws >> c

or this:

std::string q; getline(cin, q);  for(i = 0; < n && < q.size(); i++) {   if (q[i] != s[i])      ... }