std::strcspn (3) - Linux Man Pages

std::strcspn: std::strcspn

NAME

std::strcspn - std::strcspn

Synopsis


Defined in header <cstring>
size_t strcspn( const char *dest, const char *src );


Returns the length of the maximum initial segment of the byte string pointed to by dest, that consists of only the characters not found in byte string pointed to by src.
The function name stands for "complementary span"

Parameters


dest - pointer to the null-terminated byte string to be analyzed
src - pointer to the null-terminated byte string that contains the characters to search for

Return value


The length of the maximum initial segment that contains only characters not found in the byte string pointed to by src

Example


// Run this code


  #include <string>
  #include <cstring>
  #include <iostream>


  const char* invalid = "*$#";
  int main()
  {
      std::string s = "abcde312$#@";


      size_t valid_len = std::strcspn(s.c_str(), invalid);
      if(valid_len != s.size())
         std::cout << "'" << s << "' contains invalid chars starting at position "
                   << valid_len << '\n';
  }

Output:


  'abcde312$#@' contains invalid chars starting at position 8

See also


              returns the length of the maximum initial segment that consists
strspn of only the characters found in another byte string
              (function)
              returns the length of the maximum initial segment that consists
wcscspn of only the wide not found in another wide string
              (function)
              finds the first location of any character from a set of separators
strpbrk (function)
              find first occurrence of characters
find_first_of (public member function of std::basic_string<CharT,Traits,Allocator>)