...
| Code Block | ||
|---|---|---|
| ||
IN:
A = reason code:
SR_SUS ($01) Save user screen
SR_RUS ($02) Restore user screen
SR_WPD ($03) Write parameter data (mailbox)
SR_RPD ($04) Read parameter data (mailbox)
SR_FUS ($05) Free user screen
SR_CRM ($06) Remove card (not implemented)
SR_CIN ($07) Insert card (not implemented)
SR_PWT ($08) Page wait
SR_RND ($09) Occasionally a random number
(system
use) BC, DE, HL, IX = arguments
OUT, if call successful:
Fc = 0
returned values depend on A(in)
OUT, if call failed:
Fc = 1
A = error code:
RC_UNK ($03), unknown request
RC_BAD ($04), bad arguments
RC_HAND ($08), bad handle
RC_ROOM ($07), no room
RC_ESC ($01), with SR_PWT
RC_SUSP ($69), with SR_PWT
RC_DRAW ($66), with SR_PWT
RC_QUIT ($67), with SR_PWT |
...
The return value (random number) only changes when certain operating system functions occur in between calls to OS_Sr. Repeated fetching a random number may well result in the same value being returned!.
Fixed and improved since OZ 5.0 using an xor-shift algorithm.
SR_WPD
| Code Block | ||||
|---|---|---|---|---|
| ||||
IN:
DE = name of information type (null-terminated)
DE = 0, clear mailbox
BHL = extended pointer to information
C = length of information
OUT:
Fc = 0, successful
Registers changed after return:
A.BCDEHL/IXIY same
.F....../.... different |
...
Mailboxing functionality is explained in detail in Application Static Structures.