Synopsis 

#include <string.h>
char *strtok(char *source, const char *delimiters)
char *strtok_r(char *source, const char *delimiters,
    char **lasts)


Description
The strtok function is used to isolate sequential tokens in a null-terminated string, *source. These tokens are delimited in the string by at least one of the characters in *delimiters. The first time that strtok is called, *source should be specified; subsequent calls, wishing to obtain further tokens from the same string, should pass a null pointer instead. The separator string, *delimiters, must be supplied each time, and may change between calls. 

The strtok function returns a pointer to the beginning of each subsequent token in the string, after replacing the separator character itself with a NUL character. When no more tokens remain, a null pointer is returned. 

The strtok_r function has the same behavior as strtok, except a pointer to placeholder *[lasts> must be supplied by the caller. 


Returns
strtok returns a pointer to the next token, or NULL if no more tokens can be found. 


Portability
strtok is ANSI C. 

strtok requires no supporting OS subroutines. 



