text: /*
  FUNCTION
  	<<strtok>>, <<strtok_r>>, <<strsep>>---get next token from a string
  
  INDEX
  	strtok
  
  INDEX
  	strtok_r
  
  INDEX
  	strsep
  
  ANSI_SYNOPSIS
  	#include <string.h>
        	char *strtok(char *restrict <[source]>,
                       const char *restrict <[delimiters]>)
        	char *strtok_r(char *restrict <[source]>,
                         const char *restrict <[delimiters]>,
                         char **<[lasts]>)
        	char *strsep(char **<[source_ptr]>, const char *<[delimiters]>)
  
  TRAD_SYNOPSIS
  	#include <string.h>
  	char *strtok(<[source]>, <[delimiters]>)
  	char *<[source]>;
  	char *<[delimiters]>;
  
  	char *strtok_r(<[source]>, <[delimiters]>, <[lasts]>)
  	char *<[source]>;
  	char *<[delimiters]>;
  	char **<[lasts]>;
  
  	char *strsep(<[source_ptr]>, <[delimiters]>)
  	char **<[source_ptr]>;
  	char *<[delimiters]>;
  
  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 null 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.
  
  	The <<strsep>> function is similar in behavior to <<strtok>>, except
  	a pointer to the string pointer must be supplied <<<[source_ptr]>>> and
  	the function does not skip leading delimiters.  When the string starts
  	with a delimiter, the delimiter is changed to the null character and
  	the empty string is returned.  Like <<strtok_r>> and <<strtok>>, the
  	<<*<[source_ptr]>>> is updated to the next character following the
  	last delimiter found or NULL if the end of string is reached with
  	no more delimiters.
  
  RETURNS
  	<<strtok>>, <<strtok_r>>, and <<strsep>> all return a pointer to the 
  	next token, or <<NULL>> if no more tokens can be found.  For
  	<<strsep>>, a token may be the empty string.
  
  NOTES
  	<<strtok>> is unsafe for multi-threaded applications.  <<strtok_r>>
  	and <<strsep>> are thread-safe and should be used instead.
  
  PORTABILITY
  <<strtok>> is ANSI C.
  <<strtok_r>> is POSIX.
  <<strsep>> is a BSD extension.
  
  <<strtok>>, <<strtok_r>>, and <<strsep>> require no supporting OS subroutines.
  
  QUICKREF
  	strtok ansi impure
  */
  
  /* undef STRICT_ANSI so that strtok_r prototype will be defined */
  #undef  __STRICT_ANSI__
  #include <string.h>
  #include <_ansi.h>
  #include <reent.h>
  
  #ifndef _REENT_ONLY
  
  extern char *__strtok_r (char *, const char *, char **, int);
  
  char *
  _DEFUN (strtok, (s, delim),
  	register char *__restrict s _AND
  	register const char *__restrict delim)
  {
  	struct _reent *reent = _REENT;
  
  	_REENT_CHECK_MISC(reent);
  	return __strtok_r (s, delim, &(_REENT_STRTOK_LAST(reent)), 1);
  }
  #endif
  