fiopen — Opens a file in a specific mode.
ihandle -- a number which specifies this file.
ifilename -- the output file's name (in double-quotes).
imode -- choose the mode of opening the file. imode can be a value chosen among the following:
0 - open a text file for writing
1 - open a text file for reading
2 - open a binary file for writing
3 - open a binary file for reading
fiopen opens a file to be used by the fout family of opcodes. It is safer to use it in the header section, external to any instruments. It returns a number, ihandle, which unequivocally refers to the opened file.
If fiopen is called on an already open file, it just returns the same handle again, and does not close the file.
Notice that fout and foutk can use either a string containing a file pathname, or a handle-number generated by fiopen. Whereas, with fouti and foutir, the target file can be only specified by means of a handle-number.