Defined in header
long strtol( const char *str, char **str_end, int base );
long strtol( const char *restrict str, char **restrict str_end, int base );
long long strtoll( const char *restrict str, char **restrict str_end, int base );
Interprets an integer value in a byte string pointed to by
Function discards any whitespace characters (as identified by calling
isspace()) until first non-whitespace character is found. Then it takes as many characters as possible to form a valid base-n (where n=base) integer number representation and converts them to an integer value. The valid integer value consists of the following parts:
- (optional) plus or minus sign
- (optional) prefix (
0) indicating octal base (applies only when the base is 8 or 0)
- (optional) prefix (
0X) indicating hexadecimal base (applies only when the base is 16 or 0)
- a sequence of digits
The set of valid digits for base-2 integer is
01, for base-3 integer is
012, and so on. For bases larger than
10, valid digits include alphabetic characters, starting from
Aa for base-11 integer, to
Zz for base-36 integer. The case of the characters is ignored.
Additional numeric formats may be accepted by the currently installed C locale.
If the value of base is 0, the numeric base is auto-detected: if the prefix is
0, the base is octal, if the prefix is
0X, the base is hexadecimal, otherwise the base is decimal.
The functions sets the pointer pointed to by
str_end to point to the character past the last character interpreted. If
str_end is NULL, it is ignored.
str is empty or does not have the expected form, no conversion is performed, and (if
str_end is not NULL) the value of
str is stored in the object pointed to by
|str||-||pointer to the null-terminated byte string to be interpreted|
|str_end||-||pointer to a pointer to character.|
|base||-||base of the interpreted integer value|
- If successful, an integer value corresponding to the contents of
- If the converted value falls out of range of corresponding return type, a range error occurs (setting errno to ERANGE) and LONG_MAX, LONG_MIN, LLONG_MAX or LLONG_MIN is returned.
- If no conversion can be performed, 0 is returned.
|This section is incomplete|
Reason: no example
| converts a byte string to an integer value |
| converts a byte string to an unsigned integer value |
C++ documentation for strtol, strtoll