string.h library

#include <string.h>

• void *memcpy(void *sl, const void *s2, size_t n);
  copies n characters from the object pointed to by s2 into the object pointed to by s1. Returns the value of s1.
• void *memmove(void *s1, const void *s2, size_t n);
  copies n characters from the object pointed to by s2 into the object pointed to by s1. Returns the value of s1.
• char *strcpy(char *s1, const char *s2);
  copies the string pointed to by s2 including the null terminator into the array pointed to by s1. Returns the value of s1.
• char *strncpy(char *s1, const char *s2, size_t n);
  copies up n characters (copies no characters after a null terminator just appends null terminators until n characters have been put in s1) from the array pointed to by s2 to the array pointed to by s1. Will only copy a null terminator, will NOT automatically append one. Returns the value of s1.
• char *strcat(char *s1, const char *s2);
  
• char *strncat(char *s1, const char *s2, size_t n);
  
• int memcmp(const void *s1, const void *s2, size_t n);
  
• int strcmp(const char *s1, const *s2);
  
• int strcoll(const char *s1, const char *s2);
  
• int strncmp(const char *s2, const char *s2, size_t n);
  
• size_t strxfrm(char *s2, const char *s2, size_t n);
  
• void *memchr(const void *s, int c, size_t n);
  
• char *strchr(const char *s, int c);
  
• size_t strcxpn(const char *s1, const char *s2);
  
• char *strpbrk(const char *s1, const char *s2);
  
• char *strrchr(const char *s, int c);
  
• size_t strspn(const char *s1, const char *s2);
  
• char *strstr(const char *s1, const char *s2);
  
• char *strtok(char *s1, const char *s2);
  
• void *memset(void (s, int c, size_t n);
  
• void *strerror(int errnum);
  
• size_t strlen(const char *s);