1.\" $NetBSD: strtoi.3,v 1.3 2015/07/11 15:50:56 wiz 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. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" from: @(#)strtol.3 8.1 (Berkeley) 6/4/93 35.\" 36.\" Created by Kamil Rytarowski, based on ID: 37.\" NetBSD: strtol.3,v 1.31 2015/03/11 09:57:35 wiz Exp 38.\" 39.Dd April 30, 2015 40.Dt STRTOI 3 41.Os 42.Sh NAME 43.Nm strtoi 44.Nd convert string value to an intmax_t integer 45.Sh LIBRARY 46.Lb libc 47.Sh SYNOPSIS 48.In inttypes.h 49.Ft intmax_t 50.Fo strtoi 51.Fa "const char * restrict nptr" 52.Fa "char ** restrict endptr" 53.Fa "int base" 54.Fa "intmax_t lo" 55.Fa "intmax_t hi" 56.Fa "int *rstatus" 57.Fc 58.Sh DESCRIPTION 59The 60.Fn strtoi 61function 62converts the string in 63.Fa nptr 64to an 65.Ft intmax_t 66value. 67The 68.Fn strtoi 69function uses internally 70.Xr strtoimax 3 71and ensures that the result is always in the range [ 72.Fa lo .. 73.Fa hi 74]. 75In adddition it always places 76.Dv 0 77on success or a conversion status in the 78.Fa rstatus 79argument, avoiding the 80.Dv errno 81gymnastics the other functions require. 82The 83.Fa rstatus 84argument can be 85.Dv NULL 86if conversion status is to be ignored. 87.Pp 88The string may begin with an arbitrary amount of white space 89(as determined by 90.Xr isspace 3 ) 91followed by a single optional 92.Ql + 93or 94.Ql - 95sign. 96If 97.Fa base 98is zero or 16, 99the string may then include a 100.Ql 0x 101prefix, 102and the number will be read in base 16; otherwise, a zero 103.Fa base 104is taken as 10 (decimal) unless the next character is 105.Ql 0 , 106in which case it is taken as 8 (octal). 107.Pp 108The remainder of the string is converted to a 109.Em intmax_t 110value in the obvious manner, 111stopping at the first character which is not a valid digit 112in the given base. 113(In bases above 10, the letter 114.Ql A 115in either upper or lower case 116represents 10, 117.Ql B 118represents 11, and so forth, with 119.Ql Z 120representing 35.) 121.Pp 122If 123.Fa endptr 124is non-nil, 125.Fn strtoi 126stores the address of the first invalid character in 127.Fa *endptr . 128If there were no digits at all, however, 129.Fn strtoi 130stores the original value of 131.Fa nptr 132in 133.Fa *endptr . 134(Thus, if 135.Fa *nptr 136is not 137.Ql \e0 138but 139.Fa **endptr 140is 141.Ql \e0 142on return, the entire string was valid.) 143.Sh RETURN VALUES 144The 145.Fn strtoi 146function 147always returns the closest value in the range specified by 148the 149.Fa lo 150and 151.Fa hi 152arguments. 153.Pp 154The 155.Va errno 156value is guaranteed to be left unchanged. 157.Pp 158Errors are stored as the conversion status in the 159.Fa rstatus 160argument. 161.Sh EXAMPLES 162The following example will always return a number in 163.Dv [1..99] 164range no matter what the input is, and warn if the conversion failed. 165.Bd -literal -offset indent 166int e; 167intmax_t lval = strtoi(buf, NULL, 0, 1, 99, &e); 168if (e) 169 warnc(e, "conversion of `%s' to a number failed, using %jd", 170 buf, lval); 171.Ed 172.Sh ERRORS 173.Bl -tag -width Er 174.It Bq Er ECANCELED 175The string did not contain any characters that were converted. 176.It Bq Er EINVAL 177The 178.Ar base 179is not between 2 and 36 and does not contain the special value 0. 180.It Bq Er ENOTSUP 181The string contained non-numeric characters that did not get converted. 182In this case, 183.Fa endptr 184points to the first unconverted character. 185.It Bq Er ERANGE 186The given string was out of range; the value converted has been clamped; 187or the range given was invalid, i.e. 188.Fa lo 189\*[Gt] 190.Fa hi . 191.El 192.Sh SEE ALSO 193.Xr atof 3 , 194.Xr atoi 3 , 195.Xr atol 3 , 196.Xr atoll 3 , 197.Xr strtod 3 , 198.Xr strtoimax 3 , 199.Xr strtol 3 , 200.Xr strtoll 3 , 201.Xr strtou 3 , 202.Xr strtoul 3 , 203.Xr strtoull 3 , 204.Xr strtoumax 3 205.Sh STANDARDS 206The 207.Fn strtoi 208function is a 209.Nx 210extension. 211.Sh HISTORY 212The 213.Fn strtoi 214function first appeared in 215.Nx 7 . 216.Ox 217introduced the 218.Fn strtonum 3 219function for the same purpose, but the interface makes it impossible to 220properly differentiate illegal returns. 221.Sh BUGS 222Ignores the current locale. 223