STRTOL(3) Linux Programmer's Manual STRTOL(3)
**NAME**
strtol - convert a string to a long integer.
**SYNOPSIS**
**#include** **<stdlib.h>**
**long** **int** **strtol(const** **char** ******nptr***,** **char** *******endptr***,** **int** *base***);**
**DESCRIPTION**
The **strtol()** function converts the string in *nptr* to a
long integer value according to the given *base*, which must
be between 2 and 36 inclusive, or be the special value 0.
The string must begin with an arbitrary amount of white
space (as determined by **isspace**(3)) followed by a single
optional `+' or `-' sign. If *base* is zero or 16, the
string may then include a `0x' prefix, and the number will
be read in base 16; otherwise, a zero *base* is taken as 10
(decimal) unless the next character is `0', in which case
it is taken as 8 (octal).
The remainder of the string is converted to a long int
value in the obvious manner, stopping at the first charac-
ter which is not a valid digit in the given base. (In
bases above 10, the letter `A' in either upper or lower
case represents 10, `B' represents 11, and so forth, with
`Z' representing 35.)
If *endptr* is not NULL, **strtol()** stores the address of the
first invalid character in **endptr*. If there were no dig-
its at all, **strtol()** stores the original value of *nptr* in
**endptr*. (Thus, if **nptr* is not `\0' but ***endptr* is `\0'
on return, the entire string is valid.)
**RETURN** **VALUE**
The **strtol()** function returns the result of the conver-
sion, unless the value would underflow or overflow. If an
underflow occurs, **strtol()** returns LONG_MIN. If an over-
flow occurs, **strtol()** returns LONG_MAX. In both cases,
*errno* is set to ERANGE.
**ERRORS**
**ERANGE** The given string was out of range; the value con-
verted has been clamped.
**CONFORMING** **TO**
SVID 3, BSD 4.3, ISO 9899
**SEE** **ALSO**
**atof**(3), **atoi**(3), **atol**(3), **strtod**(3), **strtoul**(3)
**BUGS**
Ignores the current locale.
GNU 10 June 1995 1