memchr Function

Locates a character in a buffer.

Include

<string.h>

Prototype

void *memchr(const void *s, int c, size_t n);

Arguments

s

pointer to the buffer

c

character to search for

n

number of characters to check

Return Value

Returns a pointer to the location of the match if successful; otherwise, returns NULL.

Remarks

memchr stops when it finds the first occurrence of c, or after searching n number of characters.

Example

#include <string.h>
#include <stdio.h>

int main(void)
{
  char buf1[50] = "What time is it?";
  char ch1 = 'i', ch2 = 'y';
  char *ptr;
  int res;
  printf("buf1 : %s\n\n", buf1);

  ptr = memchr(buf1, ch1, 50);
if (ptr != NULL)
  {
   res = ptr - buf1 + 1;
   printf("%c found at position %d\n", ch1, res);
  }
  else
    printf("%c not found\n", ch1);
  printf("\n");

  ptr = memchr(buf1, ch2, 50);
if (ptr != NULL)
  {
    res = ptr - buf1 + 1;
    printf("%c found at position %d\n", ch2, res);
  }
  else
    printf("%c not found\n", ch2);
}

Example Output

buf1 : What time is it?

i found at position 7

y not found