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STRTOUL(3)                  BSD Programmer's Manual                 STRTOUL(3)

     strtoul, strtouq - convert a string to an unsigned long or uquad_t

     #include <&lt;stdlib.h>&gt;
     #include <&lt;limits.h>&gt;

     unsigned long
     strtoul(const char *nptr, char **endptr, int base);

     #include <&lt;sys/types.h>&gt;
     #include <&lt;stdlib.h>&gt;
     #include <&lt;limits.h>&gt;

     strtouq(const char *nptr, char **endptr, int base);

     The strtoul() function converts the string in nptr to an unsigned long
     value.  The strtouq() function converts the string in nptr to a u_quad_t
     value.  The conversion is done according to the given base, which must be
     between 2 and 36 inclusive, or be the special value 0.

     The string may begin with an arbitrary amount of white space (as deter-
     mined 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 value in the
     obvious manner, stopping at the end of the string or at the first charac-
     ter that does not produce 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 non nil, strtoul() stores the address of the first invalid
     character in *endptr. If there were no digits at all, however, strtoul()
     stores the original value of nptr in *endptr. (Thus, if *nptr is not `\0'
     but **endptr is `\0' on return, the entire string was valid.)

     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 conver-
     sion, unless the original (non-negated) value would overflow; in the lat-
     ter case, strtoul() returns ULONG_MAX and sets the global variable errno
     to ERANGE.

     [ERANGE]  The given string was out of range; the value converted has been


     The strtoul() function conforms to ANSI C X3.159-1989 (``ANSI C '').

     Ignores the current locale.

4.4BSD                           June 4, 1993                                1