strtol, strtoll, strtoimax, strtoq - convert string value to a long, long
long, intmax_t or quad_t integer
Standard C Library (libc, -lc)
#include <stdlib.h>
#include <limits.h>
long int
strtol(const char * restrict nptr, char ** restrict endptr, int base);
long long int
strtoll(const char * restrict nptr, char ** restrict endptr, int base);
#include <inttypes.h>
intmax_t
strtoimax(const char * restrict nptr, char ** restrict endptr, int base);
#include <sys/types.h>
#include <stdlib.h>
#include <limits.h>
quad_t
strtoq(const char * restrict nptr, char ** restrict endptr, int base);
The strtol() function converts the string in nptr to a long int value.
The strtoll() function converts the string in nptr to a long long int
value. The strtoimax() function converts the string in nptr to an
intmax_t value. The strtoq() function converts the string in nptr to a
quad_t value. The conversion is done according to the given base, which
must be between 2 and 36 inclusive, or be the special value 0.
The string may 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 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 `A' in either upper or lower
case represents 10, `B' represents 11, and so forth, with `Z' representing
35.)
If endptr is non nil, strtol() stores the address of the first invalid
character in *endptr. If there were no digits at all, however, strtol()
stores the original value of nptr in *endptr. (Thus, if *nptr is not
`\0' but **endptr is `\0' on return, the entire string was valid.)
The strtol() function returns the result of the conversion, unless the
value would underflow or overflow. If an underflow occurs, strtol()
returns LONG_MIN, strtoll() returns LLONG_MIN, and strtoimax() returns
INTMAX_MIN. If an overflow occurs, strtol() returns LONG_MAX, strtoll()
returns LLONG_MAX, and strtoimax() returns INTMAX_MAX. In these cases,
errno is set to ERANGE.
[ERANGE] The given string was out of range; the value converted
has been clamped.
atof(3), atoi(3), atol(3), atoll(3), strtod(3), strtoul(3), strtoull(3),
strtoumax(3)
The strtol() function conforms to ANSI X3.159-1989 (``ANSI C''). The
strtoll() and strtoimax() functions conform to .
Ignores the current locale.
BSD April 26, 2001 BSD
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