.\" Copyright (c) 1990, 1991 The Regents of the University of California. .\" All rights reserved. .\" .\" This code is derived from software contributed to Berkeley by .\" Chris Torek and the American National Standards Committee X3, .\" on Information Processing Systems. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" $OpenBSD: strtol.3,v 1.4 1999/06/29 18:36:23 aaron Exp $ .\" .Dd June 25, 1992 .Dt STRTOL 3 .Os .Sh NAME .Nm strtol, strtoq .Nd convert string value to a long or quad_t integer .Sh SYNOPSIS .Fd #include .Fd #include .Ft long .Fn strtol "const char *nptr" "char **endptr" "int base" .Fd #include .Fd #include .Fd #include .Ft quad_t .Fn strtoq "const char *nptr" "char **endptr" "int base" .Sh DESCRIPTION The .Fn strtol function converts the string in .Fa nptr to a .Li long value. The .Fn strtoq function converts the string in .Fa nptr to a .Li quad_t value. The conversion is done according to the given .Fa base , which must be between 2 and 36 inclusive, or be the special value 0. .Pp The string may begin with an arbitrary amount of white space (as determined by .Xr isspace 3 ) followed by a single optional .Ql + or .Ql - sign. If .Fa base is zero or 16, the string may then include a .Ql 0x prefix, and the number will be read in base 16; otherwise, a zero .Fa base is taken as 10 (decimal) unless the next character is .Ql 0 , in which case it is taken as 8 (octal). .Pp The remainder of the string is converted to a .Li long value in the obvious manner, stopping at the first character which is not a valid digit in the given base. (In bases above 10, the letter .Ql A in either upper or lower case represents 10, .Ql B represents 11, and so forth, with .Ql Z representing 35.) .Pp If .Fa endptr is non nil, .Fn strtol stores the address of the first invalid character in .Fa *endptr . If there were no digits at all, however, .Fn strtol stores the original value of .Fa nptr in .Fa *endptr . (Thus, if .Fa *nptr is not .Ql \e0 but .Fa **endptr is .Ql \e0 on return, the entire string was valid.) .Sh RETURN VALUES The .Fn strtol function returns the result of the conversion, unless the value would underflow or overflow. If an underflow occurs, .Fn strtol returns .Dv LONG_MIN . If an overflow occurs, .Fn strtol returns .Dv LONG_MAX . In both cases, .Va errno is set to .Er ERANGE . .Sh ERRORS .Bl -tag -width Er .It Bq Er ERANGE The given string was out of range; the value converted has been clamped. .El .Sh SEE ALSO .Xr atof 3 , .Xr atoi 3 , .Xr atol 3 , .Xr strtod 3 , .Xr strtoul 3 .Sh STANDARDS The .Fn strtol function conforms to .St -ansiC . .Sh BUGS Ignores the current locale.