std::strstr

 

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Defined in header <cstring>
constchar* strstr(constchar* haystack, constchar* needle );
char* strstr(       char* haystack, constchar* needle );

Finds the first occurrence of the byte string needle in the byte string pointed to by haystack. The terminating null characters are not compared.

Parameters

haystack	-	pointer to the null-terminated byte string to examine
needle	-	pointer to the null-terminated byte string to search for

Return value

Pointer to the first character of the found substring in haystack, or a null pointer if no such character is found. If needle points to an empty string, haystack is returned.

Example

Run this code

#include <cstring>#include <iomanip>#include <iostream>   int main(){constchar* str ="Try not. Do, or do not. There is no try.";constchar* target ="not";   for(constchar* result = str;(result = std::strstr(result, target));++result)std::cout<<"Found "<<std::quoted(target)<<" starting at ("<< result - str <<"): "<<std::quoted(result)<<'\n';}

Output:

Found "not" starting at (4): "not. Do, or do not. There is no try." Found "not" starting at (19): "not. There is no try."

See also

find	finds the first occurrence of the given substring (public member function of std::basic_string<CharT,Traits,Allocator>)
wcsstr	finds the first occurrence of a wide string within another wide string (function)
strchr	finds the first occurrence of a character (function)
strrchr	finds the last occurrence of a character (function)
C documentation for strstr