Writing to a file. (PHP)

[Nasimov]

It's possible to ammend data within a file vs. just adding data to the beginning or the end of the file? Mean to change something in the "middle" of the file.
Thanks.

[redhead]

It's highly unlikely to be possible, the IO system won't know how to handle it.
You write to a file pointer, yet you expect the IO system to move the remaining bytes pointed at, automaticaly as you write to the current position.

I don't see how this can be handled by any system, without some form of temporarily storing the remaining data and then moving it back after finishing the adding.

If you're talking about changing data within the file itself, meaning overwriting already stored data, then use fopen(), fseek(), fwrite(), fclose() and you're done.