Re: How can I write/read encoded numbers into/from a file?

Thank you Chris. I finally got the solution to my problem using the pack/unpack functions as you adviced me. The solution is: <? $i = 65; $s = pack("l", $i); echo strlen($s) . "\n"; echo "***$s***\n"; ?> X-Powered-By: PHP/4.1.2 Content-type: text/html 4 ***A*** // This is "\0\0\0A" Chris wrote:

Are you trying read the string '\0\0\0\0x41' from a file? or are you trying to read these 4 bytes from a file: 00000041 ? If the latter: The pack and unpack functions are designed to do this (and more). You could also manually do it yourself with something like this: $sBuff = "\0\0\0\0x41"; // Read the data into a var $iAnswer = ord($sBuff{0}) | ord($sBuff{1}) << 8 | ord($sBuff{2}) << 16 | ord($sBuff{3}) << 24; // Get the numerical value of each byte, then shift the bytes to get the 4 byte number. (Little Endian) Chris Julio Sergio Santana wrote:

I'm just starting with PHP, and I've been browsing the whole manual to find how to solve the following problem: 1. An integer number is internally represented in 4 bytes. Say, for instance, number 65 is represented by 0x00000041, that is the string "\0\0\0\0x41", and not the string "65". 2. How can I write this representation into a file and then read back it from the file? Do you have any idea about this? Thank you, Sergio.