When calling the OSFIND routine from machine code you will need to use the absolute address &40CE. However, when CALLing this routine from BBC BASIC it is recommended that you use the BBC Micro-compatible address &FFCE.
This routine opens or closes a file. The Z80 register A contains the function code.
|Code||Description||BBC BASIC Equivalent|
|A=0||Close a file||CLOSE|
|A=&4x||Open a file for input||OPENIN|
|A=&8x||Open a file for output||OPENOUT|
|A=&Cx||Open a file for update||OPENUP|
Close a File
To close a file call OSFIND with A set to 0 and H containing the handle of the file you wish to close. If H is 0 all opened file handles are closed.
Open a File
On entry HL points to a CR-terminated filename and the upper four bits of A specify the file access mode. On exit A will contain the file handle, or 0 on error.