Razor2::Errorhandler(3) User Contributed Perl Documentation Razor2::Errorhandler(3)NAME
Razor::Errorhandler - Error handling mechanism for Razor.
SYNOPSIS
package Foo;
use Razor::Errorhandler;
@ISA = qw(Razor::Errorhandler);
sub alive {
..
..
return
$self->error ("Awake, awake! Ring the alarum bell.
Murther and treason!", $dagger)
if $self->murdered($king);
}
package main;
use Foo;
my $foo = new Foo;
$foo->alive($king) or print $foo->errstr();
# prints "Awake, awake! ... "
DESCRIPTION
Razor::Errorhandler encapsulates the error handling mechanism used by the modules in Razor bundle. Razor::Errorhandler doesn't have a
constructor and is meant to be inherited. The derived modules use its two methods, error() and errstr(), to communicate error messages to
the caller.
When a method of the derived module fails, it calls $self->error() and returns to the caller. The error message passed to error() is made
available to the caller through the errstr() accessor. error() also accepts a list of sensitive data that it wipes out (undef'es) before
returning.
The caller should never call errstr() to check for errors. errstr() should be called only when a method indicates (usually through an undef
return value) that an error has occured. This is because errstr() is never overwritten and will always contain a value after the occurance
of first error.
METHODS
error($mesage, ($wipeme, $wipemetoo))
The first argument to error() is $message which is placed in $self->{errstr} and the remaining arguments are interpretted as variables
containing sensitive data that are wiped out from the memory. error() always returns undef.
errstr()
errstr() is an accessor method for $self->{errstr}.
AUTHOR
Vipul Ved Prakash, <mail@vipul.net>
SEE ALSO Razor::Client(3)perl v5.12.1 2005-08-03 Razor2::Errorhandler(3)
Check Out this Related Man Page
STRTONUM(3) BSD Library Functions Manual STRTONUM(3)NAME
strtonum -- reliably convert string value to an integer
SYNOPSIS
#include <stdlib.h>
long long
strtonum(const char *nptr, long long minval, long long maxval, const char **errstr);
DESCRIPTION
The strtonum() function converts the string in nptr to a long long value. The strtonum() function was designed to facilitate safe, robust
programming and overcome the shortcomings of the atoi(3) and strtol(3) family of interfaces.
The string may begin with an arbitrary amount of whitespace (as determined by isspace(3)) followed by a single optional '+' or '-' sign.
The remainder of the string is converted to a long long value according to base 10.
The value obtained is then checked against the provided minval and maxval bounds. If errstr is non-null, strtonum() stores an error string
in *errstr indicating the failure.
RETURN VALUES
The strtonum() function returns the result of the conversion, unless the value would exceed the provided bounds or is invalid. On error, 0
is returned, errno is set, and errstr will point to an error message. On success, *errstr will be set to NULL; this fact can be used to dif-
ferentiate a successful return of 0 from an error.
EXAMPLES
Using strtonum() correctly is meant to be simpler than the alternative functions.
int iterations;
const char *errstr;
iterations = strtonum(optarg, 1, 64, &errstr);
if (errstr != NULL)
errx(1, "number of iterations is %s: %s", errstr, optarg);
The above example will guarantee that the value of iterations is between 1 and 64 (inclusive).
ERRORS
[ERANGE] The given string was out of range.
[EINVAL] The given string did not consist solely of digit characters.
[EINVAL] The supplied minval was larger than maxval.
If an error occurs, errstr will be set to one of the following strings:
too large The result was larger than the provided maximum value.
too small The result was smaller than the provided minimum value.
invalid The string did not consist solely of digit characters.
SEE ALSO atof(3), atoi(3), atol(3), atoll(3), sscanf(3), strtod(3), strtol(3), strtoul(3)STANDARDS
The strtonum() function is a BSD extension. The existing alternatives, such as atoi(3) and strtol(3), are either impossible or difficult to
use safely.
HISTORY
The strtonum() function first appeared in OpenBSD 3.6.
BSD April 29, 2004 BSD