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: src/lib/libc/stdlib/strtoul.3,v 1.3.2.7 2002/01/21 12:30:34 ru Exp $ 38.\" $DragonFly: src/lib/libc/stdlib/strtoul.3,v 1.2 2003/06/17 04:26:46 dillon Exp $ 39.\" 40.Dd June 4, 1993 41.Dt STRTOUL 3 42.Os 43.Sh NAME 44.Nm strtoul , strtoull , strtouq 45.Nd "convert a string to an" 46.Vt "unsigned long" , "unsigned long long" , 47or 48.Vt u_quad_t 49integer 50.Sh LIBRARY 51.Lb libc 52.Sh SYNOPSIS 53.In stdlib.h 54.In limits.h 55.Ft "unsigned long" 56.Fn strtoul "const char *nptr" "char **endptr" "int base" 57.Ft "unsigned long long" 58.Fn strtoull "const char *nptr" "char **endptr" "int base" 59.In sys/types.h 60.In stdlib.h 61.In limits.h 62.Ft u_quad_t 63.Fn strtouq "const char *nptr" "char **endptr" "int base" 64.Sh DESCRIPTION 65The 66.Fn strtoul 67function 68converts the string in 69.Fa nptr 70to an 71.Vt "unsigned long" 72value. 73The 74.Fn strtoull 75function 76converts the string in 77.Fa nptr 78to an 79.Vt "unsigned long long" 80value. 81The 82.Fn strtouq 83function 84converts the string in 85.Fa nptr 86to a 87.Vt u_quad_t 88value. 89The conversion is done according to the given 90.Fa base , 91which must be between 2 and 36 inclusive, 92or be the special value 0. 93.Pp 94The string may begin with an arbitrary amount of white space 95(as determined by 96.Xr isspace 3 ) 97followed by a single optional 98.Ql + 99or 100.Ql - 101sign. 102If 103.Fa base 104is zero or 16, 105the string may then include a 106.Dq Li 0x 107prefix, 108and the number will be read in base 16; otherwise, a zero 109.Fa base 110is taken as 10 (decimal) unless the next character is 111.Ql 0 , 112in which case it is taken as 8 (octal). 113.Pp 114The remainder of the string is converted to an 115.Vt "unsigned long" 116value in the obvious manner, 117stopping at the end of the string 118or at the first character that does not produce a valid digit 119in the given base. 120(In bases above 10, the letter 121.Ql A 122in either upper or lower case 123represents 10, 124.Ql B 125represents 11, and so forth, with 126.Ql Z 127representing 35.) 128.Pp 129If 130.Fa endptr 131is not 132.Dv NULL , 133.Fn strtoul 134stores the address of the first invalid character in 135.Fa *endptr . 136If there were no digits at all, however, 137.Fn strtoul 138stores the original value of 139.Fa nptr 140in 141.Fa *endptr . 142(Thus, if 143.Fa *nptr 144is not 145.Ql \e0 146but 147.Fa **endptr 148is 149.Ql \e0 150on return, the entire string was valid.) 151.Sh RETURN VALUES 152The 153.Fn strtoul 154function 155returns either the result of the conversion 156or, if there was a leading minus sign, 157the negation of the result of the conversion, 158unless the original (non-negated) value would overflow; 159in the latter case, 160.Fn strtoul 161returns 162.Dv ULONG_MAX . 163The 164.Fn strtoull 165function 166returns either the result of the conversion 167or, if there was a leading minus sign, 168the negation of the result of the conversion, 169unless the original (non-negated) value would overflow; 170in the latter case, 171.Fn strtoull 172returns 173.Dv ULLONG_MAX . 174In all cases, 175.Va errno 176is set to 177.Er ERANGE . 178.Sh ERRORS 179.Bl -tag -width Er 180.It Bq Er ERANGE 181The given string was out of range; the value converted has been clamped. 182.El 183.Sh SEE ALSO 184.Xr strtol 3 185.Sh STANDARDS 186The 187.Fn strtoul 188function 189conforms to 190.St -isoC . 191The 192.Fn strtoull 193function 194conforms to 195.St -isoC-99 . 196The 197.Bx 198.Fn strtouq 199function is deprecated. 200.Sh BUGS 201Ignores the current locale. 202