1.\" $NetBSD: strtol.3,v 1.6 1995/12/28 08:52:53 thorpej Exp $ 2.\" 3.\" Copyright (c) 1990, 1991 The Regents of the University of California. 4.\" 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: @(#)strtol.3 5.4 (Berkeley) 6/25/92 39.\" 40.Dd June 25, 1992 41.Dt STRTOL 3 42.Os 43.Sh NAME 44.Nm strtol, strtoq 45.Nd convert string value to a long or quad_t integer 46.Sh SYNOPSIS 47.Fd #include <stdlib.h> 48.Fd #include <limits.h> 49.Ft long 50.Fn strtol "const char *nptr" "char **endptr" "int base" 51 52.Fd #include <sys/types.h> 53.Fd #include <stdlib.h> 54.Fd #include <limits.h> 55.Ft quad_t 56.Fn strtoq "const char *nptr" "char **endptr" "int base" 57.Sh DESCRIPTION 58The 59.Fn strtol 60function 61converts the string in 62.Fa nptr 63to a 64.Em long 65value. 66The 67.Fn strtoq 68function 69converts the string in 70.Fa nptr 71to a 72.Em quad_t 73value. 74The conversion is done according to the given 75.Fa base , 76which must be between 2 and 36 inclusive, 77or be the special value 0. 78.Pp 79The string may begin with an arbitrary amount of white space 80(as determined by 81.Xr isspace 3 ) 82followed by a single optional 83.Ql + 84or 85.Ql - 86sign. 87If 88.Fa base 89is zero or 16, 90the string may then include a 91.Ql 0x 92prefix, 93and the number will be read in base 16; otherwise, a zero 94.Fa base 95is taken as 10 (decimal) unless the next character is 96.Ql 0 , 97in which case it is taken as 8 (octal). 98.Pp 99The remainder of the string is converted to a 100.Em long 101value in the obvious manner, 102stopping at the first character which is not 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 strtol 117stores the address of the first invalid character in 118.Fa *endptr . 119If there were no digits at all, however, 120.Fn strtol 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 strtol 137function 138returns the result of the conversion, 139unless the value would underflow or overflow. 140If an underflow occurs, 141.Fn strtol 142returns 143.Dv LONG_MIN . 144If an overflow occurs, 145.Fn strtol 146returns 147.Dv LONG_MAX . 148In both cases, 149.Va errno 150is set to 151.Er ERANGE . 152.Sh ERRORS 153.Bl -tag -width Er 154.It Bq Er ERANGE 155The given string was out of range; the value converted has been clamped. 156.El 157.Sh SEE ALSO 158.Xr atof 3 , 159.Xr atoi 3 , 160.Xr atol 3 , 161.Xr strtod 3 , 162.Xr strtoul 3 163.Sh STANDARDS 164The 165.Fn strtol 166function 167conforms to 168.St -ansiC . 169.Sh BUGS 170Ignores the current locale. 171