In C, the **`strtok()` function** is used to split a string into a series of tokens based on a particular delimiter. A token is a substring extracted from the original string.

## Syntax
The general syntax for the `strtok()` function is:


char *strtok(char *str, const char *delim)

### Parameters
Let's look at the parameters the `strtok()` function takes as input:

* **str:** The string which is to be split
* **delim:** The character on the basis of which the split will be done

### Return value
The function performs one split and returns a pointer to the token split up. A null pointer is returned if the string cannot be split. 

## Example
Let's start off by a simple example!

### 1. Extracting a single token

The following piece of code will just split up the *Hello world* string in two and will return the first token extracted from the function.


#include<stdio.h>
#include <string.h>

int main() {
   char string[50] = "Hello world";
   // Extract the first token
   char * token = strtok(string, " ");
   printf( " %s\n", token ); //printing the token
   return 0;
}

### 2. Extracting all possible tokens
To find all possible splits of the string, based on a given delimiter, the function needs to be called in a loop. See the example below to see how this works.

Let's see how we can split up a sentence on each occurrence of the white space character:

#include<stdio.h>
#include <string.h>

int main() {
   char string[50] = "Hello! We are learning about strtok";
   // Extract the first token
   char * token = strtok(string, " ");
   // loop through the string to extract all other tokens
   while( token != NULL ) {
      printf( " %s\n", token ); //printing each token
      token = strtok(NULL, " ");
   }
   return 0;
}

Splitting a string using strtok() in C

Syntax

Parameters

Return value

Example

1. Extracting a single token

2. Extracting all possible tokens