Opens a file in memory so that it may be read from. Note that the file is seen as an octet stream, encoding doesn’t matter from this point of view. File may be read and written at random locations.
The id of the file that was opened. The id has no meaning beyond the script.
"invalid": if the path is invalid
"cannot_work_on_directory": if the path is a directory, in fact, and not a file
"unresolvable": if the file cannot be resolved
"notfound": if the file is not found
int fid = open(filename); //fileOpen
fileClose(fid);//full name of the routine