1STRTOL(3) Library Functions Manual STRTOL(3)
2
6 strtol - convert string value to a long
7
9 #include <stdlib.h>
10 #include <limits.h>
11 long
13 strtol(nptr, endptr, base)
14 char *nptr;
15 char **endptr;
16 int base;
17
19 The strtol() function converts the string in nptr to a long value. The
20 conversion is done according to the given base, which must be between 2
21 and 36 inclusive, or be the special value 0.
22 The string may begin with an arbitrary amount of white space (as deter‐
24 mined by isspace(3)) followed by a single optional `+' or `-' sign. If
25 base is zero or 16, the string may then include a `0x' prefix, and the
26 number will be read in base 16; otherwise, a zero base is taken as 10
27 (decimal) unless the next character is `0', in which case it is taken
28 as 8 (octal).
29 The remainder of the string is converted to a long value in the obvious
31 manner, stopping at the first character which is not a valid digit in
32 the given base. (In bases above 10, the letter `A' in either upper or
33 lower case represents 10, `B' represents 11, and so forth, with `Z'
34 representing 35.)
35 If endptr is non nil, strtol() stores the address of the first invalid
37 character in *endptr . If there were no digits at all, however, str‐
38 tol() stores the original value of nptr in *endptr. (Thus, if *nptr is
39 not `\0' but **endptr is `\0' on return, the entire string was valid.)
40
42 The strtol() function returns the result of the conversion, unless the
43 value would underflow or overflow. If an underflow occurs, strtol()
44 returns LONG_MIN. If an overflow occurs, strtol() returns LONG_MAX.
45 In both cases, errno is set to ERANGE .
46
48 [ERANGE] The given string was out of range; the value converted
49 has been clamped.
50
52 atof(3), atoi(3), atol(3), strtoul(3)
53
55 The strtol() function conforms to ANSI C X3.159-1989 (``ANSI C'').
56
58 Ignores the current locale.
594.4 Berkeley Distribution January 12, 1996 STRTOL(3)