#ifndef STRING_H_
#define STRING_H_

#include <stddef.h>

extern const char *strerror(int errnum);
extern const char *strerror_code(int errnum);

extern size_t strlen(const char *s);

extern int strcmp(const char *s1, const char *s2);
extern int strncmp(const char *s1, const char *s2, unsigned long n);

extern void *memset(void *str, int c, size_t n);
extern void *memcpy(void *dst, const void *src, size_t len);

extern char *strdup(char *s);

#endif