C in a Nutshell

Name

memchr

Synopsis

Searches a memory block for a given byte value

#include <string.h>
void *memchr( const void *buffer, int c, size_t n );

The memchr() function searches for a byte with the value of c in a buffer of n bytes beginning at the address in the pointer argument buffer. The function’s return value is a pointer to the first occurrence of the specified character in the buffer, or a null pointer if the character does not occur within the specified number of bytes. The type size_t is defined in string.h (and other header files), usually as unsigned int.

Example

char *found, buffer[4096] = "";
int ch = ' ';

fgets( buffer, sizeof(buffer), stdin );

/* Replace any spaces in the string read with underscores: */
while (( found =memchr( buffer, ch, strlen(buffer) )) != NULL )
  *found = '_';

See Also

strchr(), wmemchr()