User`s guide

File passwords are eight bytes in length. They are maintained in the XFCB Direc-
tory Label in encrypted form. To make a BDOS function call for a file that requires
a password, a program must place the password in the first eight bytes of the current
DMA, or specify it with the BDOS function, Set Default Password, prior to making
the function call.
Note: the BDOS keeps an assigned default password value until it is replaced with a
new assigned value.
2.3.8 File Date and Time Stamps
The CP/M 3 File System uses a special type of directory entry called an SFCB to
record date and time stamps for files. When a directory has been initialized for date
and time stamping, SFCBs reside in every fourth position of the directory. Each SFCB
maintains the date and time stamps for the previous three directory entries as shown
in Figure 2-3.
Figure 2-3. Directory Record with SFCB
This figure shows a directory record that contains an SFCB. Directory records consist
of four directory entries, each 32 bytes long. SFCBs always occupy the last position
of a directory record.
The SFCB directory item contains five fields. The first field is one byte long and
contains the value 21H. This value identifies the SFCB in the directory. The next
three fields, the SFCB subfields, contain the date and time stamps for their corre-
sponding FCB entries in the directory record. These fields are 10 bytes long. The last
byte of the SFCB is reserved for system use. The format of the SFCB subfields is
shown in Table 2-6.
2-23
2.3 BDOS File System CP/M 3 Programmer's Guide