String h C Tutorial

Item Value
Header filestring.h
Declarationchar *strncat(char *str1, const char *str2, size_t count);
Functionconcatenates not more than count characters of *str2 to *str1 and terminates str1 with a null.
Returnreturns *str1.
You have to ensure that str1 is large enough to hold both its str1 and str2.

#include 
  #include 
  int main(void)
  {
    char s1[80], s2[80];
    unsigned int len;
    gets(s1);
    gets(s2);
    len = 79-strlen(s2);
    strncat(s2, s1, len);
    printf(s2);
    return 0;
  }
2
1
12