ignore_user_abort
Array pack:
<?php
function pack_array($v,$a) {
return call_user_func_array(pack,array_merge(array($v),(array)$a));
}
?>
pack
(PHP 4, PHP 5)
pack — データをバイナリ文字列にパックする
説明
指定された引数を format に基づいて バイナリ文字列にパックします。
この関数のアイデアは Perl からのものであり、フォーマット指定用の コードは Perl と同様に動作します。しかし、中には存在しない書式コードもあります。 たとえば Perl の "u" は存在しません。
符号付及び符号無しの区別は関数 unpack() にのみ 影響を与えます。関数 pack() は符号付及び符号無しの フォーマットコードのどちらでも同じ結果となることに注意しましょう。
PHP は内部的に値をマシン依存の大きさの符号付の integer 値として保持することにも注意してください。 このように保持するには大きすぎる符号無しの値を与えた場合、 float に変換する際にしばしば期待外れの結果となります。
パラメータ
- format
-
フォーマット文字列は、 フォーマットコードの後にオプションの反復指定用引数が続く形式と なっています。反復指定用引数として整数値、または入力データの最後まで 反復を意味する * のどちらかを指定することができます。 a, A, h, H の場合、 反復数はそのデータ引数が取得する文字の数を指定します。反復数が @ の場合、 次のデータを置く場所の絶対位置を表します。その他の場合、反復数は データ引数が使われる数を指定し、結果のバイナリ文字列にパックされます。
現在、実装されているものを以下に示します。
pack() の書式文字 コード 説明 a NUL で埋めた文字列 A 空白で埋めた文字列 h 十六進文字列、下位ニブルが先 H 十六進文字列、上位ニブルが先 c signed char C unsigned char s signed short (常に 16 ビット、マシンのバイトオーダー) S unsigned short (常に 16 ビット、マシンのバイトオーダー) n unsigned short (常に 16 ビット、ビッグエンディアンバイトオーダー) v unsigned short (常に 16 ビット、リトルエンディアンバイトオーダー) i signed integer (サイズおよびバイトオーダーはマシン依存) I unsigned integer (サイズおよびバイトオーダーはマシン依存) l signed long (常に 32 ビット、マシンのバイトオーダー) L unsigned long (常に 32 ビット、マシンのバイトオーダー) N unsigned long (常に 32 ビット、ビッグエンディアンバイトオーダー) V unsigned long (常に 32 ビット、リトルエンディアンバイトオーダー) f float (サイズおよび表現はマシン依存) d double (サイズおよび表現はマシン依存) x NUL バイト X 1 バイト戻る @ 絶対位置まで NUL で埋める - args
-
返り値
バイナリ文字列を含むデータを返します。
例
例1 pack() の例
<?php
$binarydata = pack("nvc*", 0x1234, 0x5678, 65, 66);
?>
この結果のバイナリ文字列の長さは 6 バイト長で、バイト列 0x12, 0x34, 0x78, 0x56, 0x41, 0x42となります。
add a note
User Contributed Notespack
Anonymous
06-Jul-2008 08:17
06-Jul-2008 08:17
php at nagler-ihlein dot de
08-May-2008 11:26
08-May-2008 11:26
Be aware of format code H always padding the 0 for byte-alignment to the right (for odd count of nibbles).
So pack("H", "7") results in 0x70 (ASCII character 'p') and not in 0x07 (BELL character)
as well as pack("H*", "347") results in 0x34 ('4') and 0x70 ('p') and not 0x03 and 0x47.
Quis AT spam.to.my.devnull.quis.cx
25-Jan-2008 11:45
25-Jan-2008 11:45
<?PHP
function ntohs($port) {
$b=pack("N", $port);
return substr($b,2,2);
}
?>
I've spent a number of hours (n>=2) finding how to do this,
it works like the c function 'ntohs', used for eg the socks5 proxy protocol.
dylan at pow7 dot com
06-Sep-2007 08:00
06-Sep-2007 08:00
This is how I used pack to convert base2 to base64 since base_convert doesn't support base64
The base conversions don't work for long strings, which is why I convert 1 byte at a time
Hope this helps someone
function base2to64($base2) {
if ($remainbits = strlen($base2)%8) $base2 .= str_repeat('0',8-$remainbits);
$base64 = NULL;
for ($i=0;$i<strlen($base2);$i+=8) $base16 .= sprintf('%02x',bindec(sprintf('%08d',substr($base2,$i,8))));
return base64_encode(pack('H*',$base16));
}
function base64to2($base64) {
list($base16) = unpack('H*0',base64_decode($base64));
$base2 = NULL;
for ($i=0;$i<strlen($base16);$i++) $base2 .= sprintf('%04d',base_convert(substr($base16,$i,1),16,2));
return $base2;
}
Chr dot Eichert<moga at mx dot homelinux dot org>
16-Feb-2007 09:21
16-Feb-2007 09:21
This is how you can produce a code that is in fact a picture.
(This code is a complete tool, copy it to a file, call it 'somehow.php' and produce your pictures as hexcode).
<!--// ***Begin of File*** //-->
<form method="post" action="<?php echo $_SERVER['PHP_SELF'];?>" enctype="multipart/form-data">
<input type="file" name="thefile"><input type="submit">
</form>
<?php
$rh = fopen ($_FILES['thefile']['tmp_name'], "r");
$pb = fread($rh, 8192);
fclose($rh);
$pc = bin2hex($pb);
$pd = wordwrap($pc, 76, "\".<br /> \n \"", 1);
echo "<TT>\$hexpic=\""."$pd"."\"\n</TT>;";
?>
<!--// ***End of File*** //-->
Copy the result in your site code somewhere. For to show the code as a picture you can use something like what dirk (at) camindo de wrote ...
<?php
$hexpic=".......................
.....................";
$data = pack("H" . strlen($hexpic), $hexpic);
header("Content-Type: image/png");
// maybe your is jpeg / gif / png
header("Last-Modified: " . date("r", filectime($_SERVER['SCRIPT_FILENAME'])));
header("Content-Length: " . strlen($data));
echo $data;
?>
have fun!
dirk (at) camindo de
19-Jan-2007 08:22
19-Jan-2007 08:22
Work around newsletter tracking:
include a transparent gif (1x1 pixel) with url = track.php and parameters.
track.php has to write the parameters e.g. into a database and provides the gif - using following code:
header("Content-Type: image/gif");
header("Content-Length: 49");
echo pack('H*',
'47494638396101000100910000000000ffffffff'
.'ffff00000021f90405140002002c000000000100'
.'01000002025401003b'
);
Newdawn.dk
23-Mar-2006 09:25
23-Mar-2006 09:25
When trying to create a ZIP file using the pack function - I experienced trouble with the "a" code - It converted all chars correct from the std. ASCII charset but not more language specific like ÆøÅ.
It seems that ZIP files do not use the same HEX for these as everything else does.
The fix was a quick workaround but you'll probably get the picture:
function UniHex($str) {
// æ ø å Æ Ø Å
//These are simply one HEX code being replaced by another to correct the issue
$except = array("E6"=>"91","F8"=>"9B","E5"=>"86","C6"=>"92","D8"=>"9D", "C5"=>"8F");
for($i = 0; $i < strlen($str); $i++) {
$hex = bin2hex(substr($str, $i, 1));
if ($except[strtoupper($hex)])
$hex = $except[strtoupper($hex)];
$return .= $hex;
}
return $return;
}
And then i replaced an "a100" code with "H".strlen(uniHex($mystring))
This is like i said a quick workaround, but if you find the real reason for this i'd be happy to see it
j.s.hoekstra
14-Mar-2006 01:57
14-Mar-2006 01:57
/* Convert float from HostOrder to Network Order */
function FToN( $val )
{
$a = unpack("I",pack( "f",$val ));
return pack("N",$a[1] );
}
/* Convert float from Network Order to HostOrder */
function NToF($val )
{
$a = unpack("N",$val);
$b = unpack("f",pack( "I",$a[1]));
return $b[1];
}
Patrik Fimml
12-Oct-2005 02:42
12-Oct-2005 02:42
You will get the same effect with
<?php
function _readInt($fp)
{
return unpack('V', fread($fp, 4));
}
?>
or unpack('N', ...) for big-endianness.
20-Feb-2005 04:09
I needed to convert binary values from a file to integers.
Maybe there is something simpler, but the snippets i saw above seemed a little convoluted:
function bin2asc ($binary)
{
$val = 0;
for ($i = strlen($binary) - 1; $i >= 0; $i--) {
$ch = substr($binary, $i, 1);
$val = ($val << 8) | ord($ch);
}
return $val;
}
This was called like the following from a binary file:
function _readInt($fp)
{
return bin2asc(fread($fp, 4));
}
Note that the for loop should be reversed for network byte order instead of intel byte order. Also the conversion will work with any number of bytes, but will happily overflow.
zilinex at yahoo dot com
02-Sep-2004 03:12
02-Sep-2004 03:12
a cool function to converrt numbers to Persian numbers(utf-8)
origin: http://www.farsiweb.info/jalali/jalali.phps
function farsinum($str)
{
$ret = "";
for ($i = 0; $i < strlen($str); ++$i) {
$c = $str[$i];
if( $c >= '0' && $c <= '9' )
$out .= pack("C*", 0xDB, 0xB0 + $c);
else
$ret .= $c;
}
return $ret;
}
Jurgen Braam
03-Oct-2003 03:39
03-Oct-2003 03:39
take note: if you produce binary files using PHP on multiple platforms, that you use one of the machine-independent pack options.
This means 's' 'S' 'i' 'I' 'd' and 'f' are _EVIL_ :) Took me some time to figure out what my Excel-generator what futzing about :) Turned out the production machine was a Sun Sparc. I develop on my own x86 Linux server.
Hope this helps anyone...
c-ya,
Jurgen
mfisch[at]kaz[dot]com
11-Jul-2001 01:53
11-Jul-2001 01:53
If you are trying to do ascii <--> binary conversions like me;
you probably found that unlike the perl pack functions, these wont help too much. Attached are two functions I wrote to accomplish this task.
<br>
function bin2asc ($binary)
{
$i = 0;
while ( strlen($binary) > 3 )
{
$byte[$i] = substr($binary, 0, 8);
$byte[$i] = base_convert($byte[$i], 2, 10);
$byte[$i] = chr($byte[$i]);
$binary = substr($binary, 8);
$ascii = "$ascii$byte[$i]";
}
return $ascii;
}
<br>
function asc2bin ($ascii)
{
while ( strlen($ascii) > 0 )
{
$byte = ""; $i = 0;
$byte = substr($ascii, 0, 1);
while ( $byte != chr($i) ) { $i++; }
$byte = base_convert($i, 10, 2);
$byte = str_repeat("0", (8 - strlen($byte)) ) . $byte; # This is an endian (architexture) specific line, you may need to alter it.
$ascii = substr($ascii, 1);
$binary = "$binary$byte";
}
return $binary;
}
<br>
Im not sure these are the most efficient functions, but surely alot faster than loading up a perl interpreter for every binary conversion =)
plutus at gmx dot de
10-Aug-2000 08:14
10-Aug-2000 08:14
Note that the the upper command in perl looks like this:
$binarydata = pack ("n v c*", 0x1234, 0x5678, 65, 66);
In PHP it seems that no whitespaces are allowed in the first parameter. So if you want to convert your pack command from perl -> PHP, don't forget to remove the whitespaces!