![]() ![]() On x86, unpack MAY not yield the result you expect for UInt32 Note that the format string is something likeīe aware of the behavior of your system that PHP resides on. I think a more complete example could be: The "unpack" documentation is a little bit confusing. Let's give the array key a name, say "mykey". Now we want to go back from string "A\0\0\0" to number 65. Suppose we need to get some kind of internal representation of an integer, say 65, as a four-byte long. In my project I had no need to check for single precision floats. Note, this solution only works for doubles. On a big endian machine, it will call the workaround function. On a little endian machine, $unpack_workaround will simply point to the function unpack. If ( defined ( 'BIG_ENDIAN_MACHINE' )) $unpack_workaround = 'big_endian_unpack' If ( $endiantest != 1 ) define ( 'BIG_ENDIAN_MACHINE', 1 ) List ( $endiantest ) = array_values ( unpack ( 'L1L', pack ( 'V', 1 ))) $repeater = intval ( substr ( $f_v, 1 )) ![]() PHP doesn't have a formatting code that will change the byte order of doubles, so I wrote this workaround. I had a situation where I had to unpack a file filled with little-endian order double-floats in a way that would work on either little-endian or big-endian machines. Useful for writing and reading integers to / from files or sockets. This numerical index is known as a Code Point.Getting Started Introduction A simple tutorial Language Reference Basic syntax Types Variables Constants Expressions Operators Control Structures Functions Classes and Objects Namespaces Enumerations Errors Exceptions Fibers Generators Attributes References Explained Predefined Variables Predefined Exceptions Predefined Interfaces and Classes Predefined Attributes Context options and parameters Supported Protocols and Wrappers Security Introduction General considerations Installed as CGI binary Installed as an Apache module Session Security Filesystem Security Database Security Error Reporting User Submitted Data Hiding PHP Keeping Current Features HTTP authentication with PHP Cookies Sessions Dealing with XForms Handling file uploads Using remote files Connection handling Persistent Database Connections Command line usage Garbage Collection DTrace Dynamic Tracing Function Reference Affecting PHP's Behaviour Audio Formats Manipulation Authentication Services Command Line Specific Extensions Compression and Archive Extensions Cryptography Extensions Database Extensions Date and Time Related Extensions File System Related Extensions Human Language and Character Encoding Support Image Processing and Generation Mail Related Extensions Mathematical Extensions Non-Text MIME Output Process Control Extensions Other Basic Extensions Other Services Search Engine Extensions Server Specific Extensions Session Extensions Text Processing Variable and Type Related Extensions Web Services Windows Only Extensions XML Manipulation GUI Extensions Keyboard Shortcuts ? This help j Next menu item k Previous menu item g p Previous man page g n Next man page G Scroll to bottom g g Scroll to top g h Goto homepage g s Goto searchĪ helper class to convert integer to binary strings and vice versa. Unicode organizes all of the characters in its repertoire into code charts, and each character is given a unique numerical index. The Unicode Standard acts as an official registry of virtually all the characters we know: this includes characters from classical and historical texts, emoji, and formatting and control characters as well. In order to facilitate meaningful communication between computers across multiple languages, a standard is required so that the ones and zeros on one machine mean the same thing when they are transmitted to another. ![]() To understand strings in Elixir, we have to educate ourselves about Unicode and character encodings, specifically the UTF-8 encoding. Although strings are one of the most common data types in computer languages, they are subtly complex and are often misunderstood. In this chapter, we will gain clarity on what exactly binaries are, how they relate to strings, and what single-quoted values, 'like this', mean in Elixir. Iex > string = "hello" "hello" iex > is_binary ( string ) true ![]()
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