C library function - strtol()

Description

The C library function long int strtol(const char *str, char **endptr, int base) converts the initial part of the string in str to a long int value according to the given base, which must be between 2 and 36 inclusive, or be the special value 0.

Declaration

Following is the declaration for strtol() function.

long int strtol(const char *str, char **endptr, int base)

Parameters

• str -- This is the string containing the representation of an integral number.

• endptr -- This is the reference to an object of type char*, whose value is set by the function to the next character in str after the numerical value.

• base -- This is the base, which must be between 2 and 36 inclusive, or be the special value 0.

Return Value

This function returns the converted integral number as a long int value, else zero value is returned.

Example

The following example shows the usage of strtol() function.

#include <stdio.h>
#include <stdlib.h>

int main()
{
   char str[30] = "2030300 This is test";
   char **ptr;
   long ret;

   ret = strtol(str, ptr, 10);
   printf("The number(unsigned long integer) is %ld\n", ret);
   printf("String part is |%s|", *ptr);

   return(0);
}

Let us compile and run the above program, this will produce the following result:

The number(unsigned long integer) is 2030300
String part is | This is test|