

 
Manual Reference Pages  STRTOUL (3)
NAME
strtoul, strtoull, strtoumax, strtouq
 convert a string to an
.Vt unsigned long , unsigned long long , uintmax_t ,
or
.Vt u_quad_t
integer
CONTENTS
Library
Synopsis
Description
Return Values
Errors
See Also
Standards
LIBRARY
.Lb libc
SYNOPSIS
.In stdlib.h
.In limits.h
unsigned long
strtoul const char * restrict nptr char ** restrict endptr int base
unsigned long long
strtoull const char * restrict nptr char ** restrict endptr int base
.In inttypes.h
uintmax_t
strtoumax const char * restrict nptr char ** restrict endptr int base
.In sys/types.h
.In stdlib.h
.In limits.h
u_quad_t
strtouq const char *nptr char **endptr int base
DESCRIPTION
The
strtoul
function
converts the string in
nptr
to an
.Vt unsigned long
value.
The
strtoull
function
converts the string in
nptr
to an
.Vt unsigned long long
value.
The
strtoumax
function
converts the string in
nptr
to an
.Vt uintmax_t
value.
The
strtouq
function
converts the string in
nptr
to a
.Vt 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 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
.Vt unsigned long
value in the obvious manner,
stopping at the end of the string
or at the first character 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 not
NULL,
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.)
RETURN VALUES
The
strtoul,
strtoull,
strtoumax
and
strtouq
functions
return 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 (nonnegated) value would overflow;
in the latter case,
strtoul
returns
ULONG_MAX,
strtoull
returns
ULLONG_MAX,
strtoumax
returns
UINTMAX_MAX,
and
strtouq
returns
ULLONG_MAX.
In all cases,
errno
is set to
ERANGE.
If no conversion could be performed, 0 is returned and
the global variable
errno
is set to
EINVAL
(the last feature is not portable across all platforms).
ERRORS
[EINVAL]
 
The value of
base
is not supported or
no conversion could be performed
(the last feature is not portable across all platforms).

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


SEE ALSO
strtol(3),
strtonum(3),
wcstoul(3)
STANDARDS
The
strtoul
function
conforms to
isoC.
The
strtoull
and
strtoumax
functions
conform to
isoC99.
The
BSD
strtouq
function is deprecated.
Visit the GSP FreeBSD Man Page Interface. Output converted with manServer 1.07. 