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      std::memchr

      From cppreference.com
      <cpp‎ |string‎ |byte
       
       
       
       
      Defined in header<cstring>
      constvoid* memchr(constvoid* ptr,int ch,std::size_t count);
            void* memchr(      void* ptr,int ch,std::size_t count);

      Convertsch tounsignedchar and locates the first occurrence of that value in the initialcount bytes (each interpreted asunsignedchar) of the object pointed to byptr.

      This function behaves as if it reads the bytes sequentially and stops as soon as a matching bytes is found: if the array pointed to byptr is smaller thancount, but the match is found within the array, the behavior is well-defined.

      		(since C++17)

      Contents

      [edit]Parameters

      ptr - pointer to the object to be examined
      ch - byte to search for
      count - max number of bytes to examine

      [edit]Return value

      Pointer to the location of the byte, or a null pointer if no such byte is found.

      [edit]Example

      Search an array of characters.

      Run this code
      #include <cstring>#include <iostream> int main(){char arr[]={'a','\0','a','A','a','a','A','a'};char*pc=(char*) std::memchr(arr,'A', sizeof arr);if(pc!= nullptr)std::cout<<"search character found\n";elsestd::cout<<"search character not found\n";}

      Output:

      search character found

      [edit]See also

      finds the first occurrence of a character
      (function)[edit]
      finds the first element satisfying specific criteria
      (function template)[edit]
      C documentation formemchr
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/string/byte/memchr&oldid=152823"
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