explain_strtol_or_die(3) Library Functions Manual explain_strtol_or_die(3)NAME
explain_strtol_or_die - convert a string to a long integer and report errors
SYNOPSIS
#include <libexplain/strtol.h>
long explain_strtol_or_die(const char *nptr, char **endptr, int base);
long explain_strtol_on_error(const char *nptr, char **endptr, int base))
DESCRIPTION
The explain_strtol_or_die function is used to call the strtol(3) system call. On failure an explanation will be printed to stderr, obtained
from the explain_strtol(3) function, and then the process terminates by calling exit(EXIT_FAILURE).
The explain_strtol_on_error function is used to call the strtol(3) system call. On failure an explanation will be printed to stderr,
obtained from the explain_strtol(3) function, but still returns to the caller.
nptr The nptr, exactly as to be passed to the strtol(3) system call.
endptr The endptr, exactly as to be passed to the strtol(3) system call.
base The base, exactly as to be passed to the strtol(3) system call.
RETURN VALUE
The explain_strtol_or_die function only returns on success, see strtol(3) for more information. On failure, prints an explanation and
exits, it does not return.
The explain_strtol_on_error function always returns the value return by the wrapped strtol(3) system call.
EXAMPLE
The explain_strtol_or_die function is intended to be used in a fashion similar to the following example:
long result = explain_strtol_or_die(nptr, endptr, base);
SEE ALSO strtol(3)
convert a string to a long integer
explain_strtol(3)
explain strtol(3) errors
exit(2) terminate the calling process
COPYRIGHT
libexplain version 0.52
Copyright (C) 2009 Peter Miller
explain_strtol_or_die(3)
Check Out this Related Man Page
STRTOL(3) Linux Programmer's Manual STRTOL(3)NAME
strtol, strtoll, strtoq - convert a string to a long integer.
SYNOPSIS
#include <stdlib.h>
long int
strtol(const char *nptr, char **endptr, int base);
long long int
strtoll(const char *nptr, char **endptr, int base);
DESCRIPTION
The strtol() function converts the initial part of 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 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 not NULL, strtol() stores the address of the first invalid character in *endptr. If there were no digits at all, strtol()
stores the original value of nptr in *endptr (and returns 0). In particular, if *nptr is not ` ' but **endptr is ` ' on return, the
entire string is valid.
The strtoll() function works just like the strtol() function but returns a long long integer value.
RETURN VALUE
The strtol() function returns the result of the conversion, unless the value would underflow or overflow. If an underflow occurs, strtol()
returns LONG_MIN. If an overflow occurs, strtol() returns LONG_MAX. In both cases, errno is set to ERANGE. Precisely the same holds for
strtoll() (with LLONG_MIN and LLONG_MAX instead of LONG_MIN and LONG_MAX).
ERRORS
ERANGE The resulting value was out of range.
EINVAL (not in C99) The given base contains an unsupported value.
The implementation may also set errno to EINVAL in case no conversion was performed (no digits seen, and 0 returned).
NOTES
In locales other than the "C" locale, also other strings may be accepted. (For example, the thousands separator of the current locale may
be supported.)
BSD also has
quad_t
strtoq(const char *nptr, char **endptr, int base);
with completely analogous definition. Depending on the wordsize of the current architecture, this may be equivalent to strtoll() or to
strtol().
CONFORMING TO
strtol() conforms to SVID 3, BSD 4.3, ISO 9899 (C99) and POSIX, and strtoll() to ISO 9899 (C99) and POSIX-2001.
SEE ALSO atof(3), atoi(3), atol(3), strtod(3), strtoul(3)GNU 2002-05-30 STRTOL(3)