function
<cstdlib>

atoll

long long int atoll ( const char * str );
Convert string to long long integer
Parses the C-string str interpreting its content as an integral number, which is returned as a value of type long long int.

This function operates like atol to interpret the string, but produces numbers of type long long int (see atol for details on the interpretation process).

Parameters

str
C-string containing the representation of an integral number.

Return Value

On success, the function returns the converted integral number as a long long int value.
If no valid conversion could be performed, a zero value is returned.
If the converted value would be out of the range of representable values by a long long int, it causes undefined behavior. See strtoll for a more robust cross-platform alternative when this is a possibility.

Example

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/* atoll example */
#include <stdio.h>      /* printf, fgets */
#include <stdlib.h>     /* atoll */

int main ()
{
  long long int lli;
  char buffer[256];
  printf ("Enter a long number: ");
  fgets (buffer, 256, stdin);
  lli = atoll(buffer);
  printf ("The value entered is %lld. Its double is %lld.\n",lli,lli*2);
  return 0;
}


Output:

Enter a number: 9275806
The value entered is 9275806. Its double is 18551612.

Data races

The array pointed by str is accessed.

Exceptions (C++)

No-throw guarantee: this function never throws exceptions.

If str does not point to a valid C-string, or if the converted value would be out of the range of values representable by a long long int, it causes undefined behavior.

See also

atoi
Convert string to integer (function )
atol
Convert string to long integer (function )
strtoll
Convert string to long long integer (function )

C++