User`s guide

Table A-1. (continued)
Offset RW/RO Defint.tion
4B RW BDOS Error Mode. This field is set by BDOS Function
45, Set BDOS Error Mode.
If this byte is set to OFFH, the system returns to the
current program without displaying any error messages.
If it is set to OFEH, the system displays error messages
before returning to the current program. Otherwise, the
system terminates the program and displays error mes-
sages. See description of BDOS Function 45, Set BDOS
Error Mode, for discussion of the different error modes.
4C - 4F RW Drive Search Chain. The first byte contains the drive
number of the first drive in the chain, the second byte
contains the drive number of the second drive in the
chain, and so on, for up to four bytes. If less than four
drives are to be searched, the next byte is set to OFFH
to signal the end of the search chain. The drive values
range from 0-16, where 0 corresponds to the default
drive, while 1-16 corresponds to drives A-P, respec-
tively. The drive search chain can be displayed or set
by using the SETDEF utility (see CPIM Plus (Version 3)
Operating System User's Guide).
50 RW Temporary File Drive. This byte contains the drive
number of the temporary file drive. The drive number
ranges from 0-16, where 0 corresponds to the default
drive, while 1-16 corresponds to drives A-P, respectively.
51 RO Error drive. This byte contains the drive number of the
selected drive when the last physical or extended error
occurred.
52 - 56 RO Reserved for system use.
A-5
Appendix A System Control Block CP/M 3 Programmer's Guide