c/string/byte/strtol

Interprets an integer value in a byte string pointed to by.

The functions set the pointer pointed to by to point to the character past the last numeric character interpreted. If is a null pointer, it is ignored.

If the is empty or does not have the expected form, no conversion is performed, and (if  is not a null pointer) the value of  is stored in the object pointed to by.

Return value

 * If successful, an integer value corresponding to the contents of is returned.
 * If the converted value falls out of range of corresponding return type, a range error occurs (setting errno to erange) and long_max, long_min, llong_max or llong_min is returned.
 * If no conversion can be performed, is returned.