strstr()

Function

Scans a string for the first occurrence of a given substring.

Syntax

int strstr(string s1, string s2[, int index]);

Returns

The strstr function returns the integer offset of the first character of s2 in s1, or -1 if the substring does not occur in the string.

If index is given, the search starts at that position. Negative values are counted from the end of the string.

Example

string s1 = "This is a string", s2 = "is a";
int pos = strstr(s1, s2);
if (pos >= 0)
   printf("The substring starts at %d\n", pos);
else
   printf("The substring was not found\n");