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C Language: memchr function
(Search Memory Block for Character)

In the C Programming Language, the memchr function searches within the first n characters of the object pointed to by s for the character c. It returns a pointer to it.

Syntax

The syntax for the memchr function in the C Language is:

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

Parameters or Arguments

s

A pointer to a string where the search will be performed.

c

The value to be found.

n

The number of characters to search within the object pointed to by s.

Returns

The memchr function returns a pointer to the first occurrence of the character c within the first n characters of the object pointed to by s. If c isn't found, it returns a null pointer.

Required Header

In the C Language, the required header for the memchr function is:

#include <string.h>

Applies To

In the C Language, the memchr function can be used in the following versions:

• ANSI/ISO 9899-1990

memchr Example

Let's look at an example to see how you would use the memchr function in a C program:

/* Example using memchr by TechOnTheNet.com */

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

int main(int argc, const char * argv[])
{
    char search[] = "TechOnTheNet";
    char *ptr;

    /* Return a pointer to the first 'N' within the search string */
    ptr = (char*)memchr(search, 'N', strlen(search));

    /* If 'N' was found, print its location (This should produce "10") */
    if (ptr != NULL) printf("Found 'N' at position %ld.\n", 1+(ptr-search));
    else printf("'N' was not found.\n");

    return 0;
}

When compiled and run, this application will output:

Found 'N' at position 10.

Similar Functions

Other C functions that are similar to the memchr function:

• strchr function <string.h>

See Also

Other C functions that are noteworthy when dealing with the memchr function:

• strpbrk function <string.h>
• strrchr function <string.h>
• strstr function <string.h>