how to read first 48 bytes of a binary variable

[michaeljoser]

I have a binary variable, say $binarydata, which contains a file that was kept in a MySQL database and I need to get the first 48bytes to put in variable $header.... now how do I do this?

I read about unpack and thought it might help me but can't figure out the syntax.

anyone can help?

[devinemke]

SELECT SUBSTRING(blob, 1, 48) FROM table

[michaeljoser]

thanks for that now what if I have the $binarydata and want to extract:

first 48 bytes to a variable header$
then the next 16 bytes to another variable $type
and the next 200 bytes in another variable $body

without any mysql substring so using only php commands... is that possible?

thanks again 🙂

[devinemke]

[man]substr[/man]