strtok function

All the books that I have read, say that strtok will break a string into tokens. This is true, but a more obvious explanation is, that it will break a string into words.

strtok requires a string and the word delimiters, for example:

	   word = strtok(string, " ");
	                   A      A
	                   |      |
	                   |	  -------  Delimiters.
	                   |
	                   --------------  String to break up.


Library:   string.h

Prototype: char * strtok(char *s, const char *delim);

Syntax:	   char string []="abc def ghi";
	   char * word;

	   word=strtok(string, " ");
	   word=strtok(NULL, " ");

After the first call to strtok, word will point to abc on the second call, word will point to def

Notes:

• strtok will alter the I/P string by placing NULLS at the delimiter positions. A good habit is to copy the string to a tempary string and use the copy in the strtok call.

• More than one delimiter can be specified. So you could code:

  
  	word = strtok(string, " \t;:,");
  	                         
  

• You do not have to include \0 or NULL in the delimiter string, it is the default. If you pass the empty string, the delimiter is assumed to be null.

Examples:

Example program.

See also:

strcpy

strncpy