PHP pack() Function
❮ PHP Misc Reference
Example
Pack data into a binary string:
<?php
echo pack("C3",80,72,80);
?>
Run example »
Definition and Usage
The pack() function packs data into a binary string.
Syntax
| Parameter |
Description |
| format |
Required. Specifies the format to use when packing data.
Possible values:
- a - NUL-padded string
- A - SPACE-padded string
- h - Hex string, low nibble first
- H - Hex string, high nibble first
- c - signed char
- C - unsigned char
- s - signed short (always 16 bit, machine byte order)
- S - unsigned short (always 16 bit, machine byte order)
- n - unsigned short (always 16 bit, big endian byte order)
- v - unsigned short (always 16 bit, little endian byte order)
- i - signed integer (machine dependent size and byte order)
- I - unsigned integer (machine dependent size and byte order)
- l - signed long (always 32 bit, machine byte order)
- L - unsigned long (always 32 bit, machine byte order)
- N - unsigned long (always 32 bit, big endian byte order)
- V - unsigned long (always 32 bit, little endian byte order)
- f - float (machine dependent size and representation)
- d - double (machine dependent size and representation)
- x - NUL byte
- X - Back up one byte
- Z - NUL-padded string
- @ - NUL-fill to absolute position
|
| args+ |
Optional. Specifies one or more arguments to be packed |
Technical Details
| Return Value: |
Returns a binary string containing data |
| PHP Version: |
4+ |
| Changelog: |
The "Z" code was added in PHP 5.5 with the same functionality as "a" for Perl compatibility |
More Examples
Example 1
Pack data into a binary string:
<?php
echo pack("C*",80,72,80);
?>
Run example »
❮ PHP Misc Reference
