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`strtol'--string to long
long strtol(const char *S, char **PTR,int BASE);
long _strtol_r(void *REENT,
const char *S, char **PTR,int BASE);
The function `strtol' converts the string `*S' to a `long'. First, it
breaks down the string into three parts: leading whitespace, which is
ignored; a subject string consisting of characters resembling an
integer in the radix specified by BASE; and a trailing portion
consisting of zero or more unparseable characters, and always including
the terminating null character. Then, it attempts to convert the
subject string into a `long' and returns the result.
If the value of BASE is 0, the subject string is expected to look
like a normal C integer constant: an optional sign, a possible ``0x''
indicating a hexadecimal base, and a number. If BASE is between 2 and
36, the expected form of the subject is a sequence of letters and
digits representing an integer in the radix specified by BASE, with an
optional plus or minus sign. The letters `a'-`z' (or, equivalently,
`A'-`Z') are used to signify values from 10 to 35; only letters whose
ascribed values are less than BASE are permitted. If BASE is 16, a
leading `0x' is permitted.
The subject sequence is the longest initial sequence of the input
string that has the expected form, starting with the first
non-whitespace character. If the string is empty or consists entirely
of whitespace, or if the first non-whitespace character is not a
permissible letter or digit, the subject string is empty.
If the subject string is acceptable, and the value of BASE is zero,
`strtol' attempts to determine the radix from the input string. A
string with a leading `0x' is treated as a hexadecimal value; a string
with a leading 0 and no `x' is treated as octal; all other strings are
treated as decimal. If BASE is between 2 and 36, it is used as the
conversion radix, as described above. If the subject string begins with
a minus sign, the value is negated. Finally, a pointer to the first
character past the converted subject string is stored in PTR, if PTR is
If the subject string is empty (or not in acceptable form), no
conversion is performed and the value of S is stored in PTR (if PTR is
The alternate function `_strtol_r' is a reentrant version. The
extra argument REENT is a pointer to a reentrancy structure.
`strtol' returns the converted value, if any. If no conversion was
made, 0 is returned.
`strtol' returns `LONG_MAX' or `LONG_MIN' if the magnitude of the
converted value is too large, and sets `errno' to `ERANGE'.
`strtol' is ANSI.
No supporting OS subroutines are required.
Created Mon Nov 8 17:42:53 2004 on tillpc with info_to_html version 0.9.6.