Reads a file, decompresses it and writes it to standard output.
readgzfile() can be used to read a file which is not in gzip format; in this case readgzfile() will directly read from the file without decompression.
The file name. This file will be opened from the filesystem and its contents written to standard output.
You can set this optional parameter to 1, if you want to search for the file in the include_path too.
Returns the number of (uncompressed) bytes read from the file. If an error occurs, FALSE is returned and unless the function was called as @readgzfile, an error message is printed.