1.\" $NetBSD: strtoul.3,v 1.9 1998/02/05 18:50:20 perry Exp $ 2.\" 3.\" Copyright (c) 1990, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" This code is derived from software contributed to Berkeley by 7.\" Chris Torek and the American National Standards Committee X3, 8.\" on Information Processing Systems. 9.\" 10.\" Redistribution and use in source and binary forms, with or without 11.\" modification, are permitted provided that the following conditions 12.\" are met: 13.\" 1. Redistributions of source code must retain the above copyright 14.\" notice, this list of conditions and the following disclaimer. 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in the 17.\" documentation and/or other materials provided with the distribution. 18.\" 3. All advertising materials mentioning features or use of this software 19.\" must display the following acknowledgement: 20.\" This product includes software developed by the University of 21.\" California, Berkeley and its contributors. 22.\" 4. Neither the name of the University nor the names of its contributors 23.\" may be used to endorse or promote products derived from this software 24.\" without specific prior written permission. 25.\" 26.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36.\" SUCH DAMAGE. 37.\" 38.\" from: @(#)strtoul.3 8.1 (Berkeley) 6/4/93 39.\" 40.Dd June 4, 1993 41.Dt STRTOUL 3 42.Os 43.Sh NAME 44.Nm strtoul , 45.Nm strtouq 46.Nd convert a string to an unsigned long or uquad_t integer 47.Sh LIBRARY 48.Lb libc 49.Sh SYNOPSIS 50.Fd #include <stdlib.h> 51.Fd #include <limits.h> 52.Ft unsigned long 53.Fn strtoul "const char *nptr" "char **endptr" "int base" 54 55.Fd #include <sys/types.h> 56.Fd #include <stdlib.h> 57.Fd #include <limits.h> 58.Ft u_quad_t 59.Fn strtouq "const char *nptr" "char **endptr" "int base" 60.Sh DESCRIPTION 61The 62.Fn strtoul 63function 64converts the string in 65.Fa nptr 66to an 67.Em unsigned long 68value. 69The 70.Fn strtouq 71function 72converts the string in 73.Fa nptr 74to a 75.Em u_quad_t 76value. 77The conversion is done according to the given 78.Fa base , 79which must be between 2 and 36 inclusive, 80or be the special value 0. 81.Pp 82The string may begin with an arbitrary amount of white space 83(as determined by 84.Xr isspace 3 ) 85followed by a single optional 86.Ql + 87or 88.Ql - 89sign. 90If 91.Fa base 92is zero or 16, 93the string may then include a 94.Ql 0x 95prefix, 96and the number will be read in base 16; otherwise, a zero 97.Fa base 98is taken as 10 (decimal) unless the next character is 99.Ql 0 , 100in which case it is taken as 8 (octal). 101.Pp 102The remainder of the string is converted to an 103.Em unsigned long 104value in the obvious manner, 105stopping at the end of the string 106or at the first character that does not produce a valid digit 107in the given base. 108(In bases above 10, the letter 109.Ql A 110in either upper or lower case 111represents 10, 112.Ql B 113represents 11, and so forth, with 114.Ql Z 115representing 35.) 116.Pp 117If 118.Fa endptr 119is non nil, 120.Fn strtoul 121stores the address of the first invalid character in 122.Fa *endptr . 123If there were no digits at all, however, 124.Fn strtoul 125stores the original value of 126.Fa nptr 127in 128.Fa *endptr . 129(Thus, if 130.Fa *nptr 131is not 132.Ql \e0 133but 134.Fa **endptr 135is 136.Ql \e0 137on return, the entire string was valid.) 138.Sh RETURN VALUES 139The 140.Fn strtoul 141function 142returns either the result of the conversion 143or, if there was a leading minus sign, 144the negation of the result of the conversion, 145unless the original (non-negated) value would overflow; 146in the latter case, 147.Fn strtoul 148returns 149.Dv ULONG_MAX 150and sets the global variable 151.Va errno 152to 153.Er ERANGE . 154.Sh ERRORS 155.Bl -tag -width Er 156.It Bq Er ERANGE 157The given string was out of range; the value converted has been clamped. 158.El 159.Sh SEE ALSO 160.Xr strtol 3 161.Sh STANDARDS 162The 163.Fn strtoul 164function 165conforms to 166.St -ansiC . 167.Sh BUGS 168Ignores the current locale. 169