STRTOUL(3) Linux Programmer's Manual STRTOUL(3)
NAME
strtoul - convert a string to an unsigned long integer.
SYNOPSIS
**#include <stdlib.h>**
**unsigned long int strtoul(const char ****nptr***, char *****endptr***,**
**int **base**)**
DESCRIPTION
The **strtoul() **function converts the string in *nptr *to an unsigned long
integer value according to the given *base*, which must be between 2 and 36
inclusive, or be the special value 0.
The string must begin with an arbitrary amount of white space (as
determined by isspace(3)) followed by a single optional `+' or `-' sign.
If *base *is zero or 16, the string may then include a `0x' prefix, and the
number will be read in base 16; otherwise, a zero *base *is taken as 10
(decimal) unless the next character is `0', in which case it is taken as
8 (octal).
The remainder of the string is converted to an unsigned long int value in
the obvious manner, stopping at the first character which is not a valid
digit in the given base. (In bases above 10, the letter `A' in either
upper or lower case represents 10, `B' represents 11, and so forth, with
`Z' representing 35.)
If *endptr *is not NULL, **strtoul() **stores the address of the first invalid
character in **endptr*. If there were no digits at all, **strtoul() **stores
the original value of *nptr *in **endptr*. (Thus, if **nptr *is not `\0' but
***endptr *is `\0' on return, the entire string is valid.)
RETURN VALUE
The **strtoul() **function returns either the result of the conversion or, if
there was a leading minus sign, the negation of the result of the
conversion, unless the original (non-negated) value would overflow; in
the latter case, **strtoul() **returns ULONG_MAX and sets the global variable
*errno *to ERANGE.
ERRORS
**ERANGE **The given string was out of range; the value converted has been
clamped.
CONFORMING TO
SVID 3, BSD 4.3, ISO 9899
SEE ALSO
atof(3), atoi(3), atol(3), strtod(3), strtol(3)
BUGS
Ignores the current locale.
GNU March 29, 1993 STRTOUL(3)