mt_srand
Number is octal?
Simple and easy:
<?php
function is_octal($x) {
return decoct(octdec($x)) == $x;
}
echo is_octal(077); // true
echo is_octal(195); // false
?>
Thanks
[]'s
octdec
(PHP 4, PHP 5)
octdec — Octal to decimal
Description
Returns the decimal equivalent of the octal number
represented by the octal_string argument.
Parameters
-
octal_string -
The octal string to convert
Return Values
The decimal representation of octal_string
Changelog
| Version | Description |
|---|---|
| 4.1.0 | The function can now convert numbers that are too large to fit into the platforms integer type, larger values are returned as float in that case. |
Examples
Example #1 octdec() example
<?php
echo octdec('77') . "\n";
echo octdec(decoct(45));
?>
The above example will output:
63 45
See Also
- decoct() - Decimal to octal
- bindec() - Binary to decimal
- hexdec() - Hexadecimal to decimal
- base_convert() - Convert a number between arbitrary bases
add a note
User Contributed Notes
octdec - [5 notes]
contato at andersonfraga dot net ¶
4 years ago
harry at disgruntledgoat dot com ¶
6 years ago
Calling the sticky bit "text" is not erroneous: On UNIX back in 1974, it instructed the operating system to retain the text segment of the program in swap space after the process exited. This speeded subsequent executions by allowing the kernel to make a single operation of moving the program from swap to real memory.
Anonymous ¶
10 years ago
The 'S' flag for Unix file access rights is badly computed in the above sample.
If the corresponding 'x' bit (exec) is not set, and the 's' bit (setgid/setuid/sticky) is set, then the flag should not be displayed as and uppercase 'S', but as a lower case 's'. Also the sticky bit (mainly used for folders with public right access rights such as /tmp to protect against deletion by non owner) is badly named ("text"?).
cubbo at quakenet dot php ¶
4 years ago
Hi, this is an attempt to explain octdec().
There is one bug, if input is not octal, it doesn't return a proper decimal.
<?php
$octal = (int) "764";
function octal_to_decimal($int)
{
$data = integer;
$i = (strlen($int) - 1);
$parse_int = str_split($int);
foreach($parse_int as $value)
{
$data += (int)($value * pow(8, $i));
$i--;
}
return $data;
}
/**
* explanation of the PHP function octdec()
*/
print octal_to_decimal($octal) . "<br />";
/**
* the PHP function octdec()
*/
print octdec($octal);
?>
meheler at searchbc dot com ¶
11 years ago
This function and decoct work great when working with file permissions. For example:
<?php
$mode = octdec('4750');
$user['suid'] = ($mode & 04000);
$user['read'] = ($mode & 00400);
$user['write'] = ($mode & 00200);
$user['execute'] = ($mode & 00100);
$group['sgid'] = ($mode & 02000);
$group['read'] = ($mode & 00040);
$group['write'] = ($mode & 00020);
$group['execute'] = ($mode & 00010);
$other['text'] = ($mode & 01000);
$other['read'] = ($mode & 00004);
$other['write'] = ($mode & 00002);
$other['execute'] = ($mode & 00001);
$attrs = array('-','-','-','-','-','-','-','-','-','-');
if ($system['dir']) $attrs[0] = 'd';
if ($user['read']) $attrs[1] = 'r';
if ($user['write']) $attrs[2] = 'w';
if ($user['execute']) $attrs[3] = 'x';
if ($user['suid']) $attrs[3] = 'S';
if ($group['read']) $attrs[4] = 'r';
if ($group['write']) $attrs[5] = 'w';
if ($group['execute']) $attrs[6] = 'x';
if ($group['sgid']) $attrs[6] = 'S';
if ($other['read']) $attrs[7] = 'r';
if ($other['write']) $attrs[8] = 'w';
if ($other['execute']) $attrs[9] = 'x';
if ($other['text']) $attrs[9] = 'T';
echo '<pre>';
echo 'Mode Decimal: ' . $mode . "\n";
echo 'Mode Octal: ' . decoct($mode) . "\n";
echo 'Mode String: ' . implode('',$attrs)."\n";
echo '</pre>';
?>
Outputs:
Mode Decimal: 2536
Mode Octal: 4750
Mode String: -rwSr-x---
-Mike