1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Chris Torek and the American National Standards Committee X3, 6.\" on Information Processing Systems. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. All advertising materials mentioning features or use of this software 17.\" must display the following acknowledgement: 18.\" This product includes software developed by the University of 19.\" California, Berkeley and its contributors. 20.\" 4. Neither the name of the University nor the names of its contributors 21.\" may be used to endorse or promote products derived from this software 22.\" without specific prior written permission. 23.\" 24.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34.\" SUCH DAMAGE. 35.\" 36.\" @(#)strtoul.3 8.1 (Berkeley) 6/4/93 37.\" $FreeBSD$ 38.\" 39.Dd June 4, 1993 40.Dt STRTOUL 3 41.Os 42.Sh NAME 43.Nm strtoul, strtouq 44.Nd convert a string to an unsigned long or uquad_t integer 45.Sh SYNOPSIS 46.Fd #include <stdlib.h> 47.Fd #include <limits.h> 48.Ft unsigned long 49.Fn strtoul "const char *nptr" "char **endptr" "int base" 50 51.Fd #include <sys/types.h> 52.Fd #include <stdlib.h> 53.Fd #include <limits.h> 54.Ft u_quad_t 55.Fn strtouq "const char *nptr" "char **endptr" "int base" 56.Sh DESCRIPTION 57The 58.Fn strtoul 59function 60converts the string in 61.Fa nptr 62to an 63.Em unsigned long 64value. 65The 66.Fn strtouq 67function 68converts the string in 69.Fa nptr 70to a 71.Em u_quad_t 72value. 73The conversion is done according to the given 74.Fa base , 75which must be between 2 and 36 inclusive, 76or be the special value 0. 77.Pp 78The string may begin with an arbitrary amount of white space 79(as determined by 80.Xr isspace 3 ) 81followed by a single optional 82.Ql + 83or 84.Ql - 85sign. 86If 87.Fa base 88is zero or 16, 89the string may then include a 90.Ql 0x 91prefix, 92and the number will be read in base 16; otherwise, a zero 93.Fa base 94is taken as 10 (decimal) unless the next character is 95.Ql 0 , 96in which case it is taken as 8 (octal). 97.Pp 98The remainder of the string is converted to an 99.Em unsigned long 100value in the obvious manner, 101stopping at the end of the string 102or at the first character that does not produce a valid digit 103in the given base. 104(In bases above 10, the letter 105.Ql A 106in either upper or lower case 107represents 10, 108.Ql B 109represents 11, and so forth, with 110.Ql Z 111representing 35.) 112.Pp 113If 114.Fa endptr 115is non nil, 116.Fn strtoul 117stores the address of the first invalid character in 118.Fa *endptr . 119If there were no digits at all, however, 120.Fn strtoul 121stores the original value of 122.Fa nptr 123in 124.Fa *endptr . 125(Thus, if 126.Fa *nptr 127is not 128.Ql \e0 129but 130.Fa **endptr 131is 132.Ql \e0 133on return, the entire string was valid.) 134.Sh RETURN VALUES 135The 136.Fn strtoul 137function 138returns either the result of the conversion 139or, if there was a leading minus sign, 140the negation of the result of the conversion, 141unless the original (non-negated) value would overflow; 142in the latter case, 143.Fn strtoul 144returns 145.Dv ULONG_MAX 146and sets the global variable 147.Va errno 148to 149.Er ERANGE . 150.Sh ERRORS 151.Bl -tag -width [ERANGE] 152.It Bq Er ERANGE 153The given string was out of range; the value converted has been clamped. 154.El 155.Sh SEE ALSO 156.Xr strtol 3 157.Sh STANDARDS 158The 159.Fn strtoul 160function 161conforms to 162.St -ansiC . 163.Sh BUGS 164Ignores the current locale. 165