1.\" $NetBSD: strtol.3,v 1.9 1998/02/05 18:50:19 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: @(#)strtol.3 8.1 (Berkeley) 6/4/93 39.\" 40.Dd June 4, 1993 41.Dt STRTOL 3 42.Os 43.Sh NAME 44.Nm strtol , 45.Nm strtoq 46.Nd convert string value to a long or quad_t integer 47.Sh LIBRARY 48.Lb libc 49.Sh SYNOPSIS 50.Fd #include <stdlib.h> 51.Fd #include <limits.h> 52.Ft long 53.Fn strtol "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 quad_t 59.Fn strtoq "const char *nptr" "char **endptr" "int base" 60.Sh DESCRIPTION 61The 62.Fn strtol 63function 64converts the string in 65.Fa nptr 66to a 67.Em long 68value. 69The 70.Fn strtoq 71function 72converts the string in 73.Fa nptr 74to a 75.Em 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 a 103.Em long 104value in the obvious manner, 105stopping at the first character which is not a valid digit 106in the given base. 107(In bases above 10, the letter 108.Ql A 109in either upper or lower case 110represents 10, 111.Ql B 112represents 11, and so forth, with 113.Ql Z 114representing 35.) 115.Pp 116If 117.Fa endptr 118is non nil, 119.Fn strtol 120stores the address of the first invalid character in 121.Fa *endptr . 122If there were no digits at all, however, 123.Fn strtol 124stores the original value of 125.Fa nptr 126in 127.Fa *endptr . 128(Thus, if 129.Fa *nptr 130is not 131.Ql \e0 132but 133.Fa **endptr 134is 135.Ql \e0 136on return, the entire string was valid.) 137.Sh RETURN VALUES 138The 139.Fn strtol 140function 141returns the result of the conversion, 142unless the value would underflow or overflow. 143If an underflow occurs, 144.Fn strtol 145returns 146.Dv LONG_MIN . 147If an overflow occurs, 148.Fn strtol 149returns 150.Dv LONG_MAX . 151In both cases, 152.Va errno 153is set to 154.Er ERANGE . 155.Sh ERRORS 156.Bl -tag -width Er 157.It Bq Er ERANGE 158The given string was out of range; the value converted has been clamped. 159.El 160.Sh SEE ALSO 161.Xr atof 3 , 162.Xr atoi 3 , 163.Xr atol 3 , 164.Xr strtod 3 , 165.Xr strtoul 3 166.Sh STANDARDS 167The 168.Fn strtol 169function 170conforms to 171.St -ansiC . 172.Sh BUGS 173Ignores the current locale. 174