ReadLineV (changes)
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Programmer's Reference Manuals
» Vectors
» Software Vector Numbers
» ReadLineV
ReadLine Vector (15)
The API of this vector depends on processor mode.
In 32bit processor modes, the API is as for OS_ReadLine32:
| Entry | |
|---|---|
| R0 | Buffer |
| R1 | Size of buffer -1 (bit31 should be ignored) |
| R2 | Lowest char allowed |
| R3 | Highest char allowed |
| R4 | Character to output + flags |
| Exit | |
|---|---|
| R0 | Preserve |
| R1 | Chars read, excluding Return |
| R2 | Preserve |
| R3 | Preserve |
| R4 | Preserve |
| C flag is set if input is terminated by an escape condition | |
In 26bit processor modes, the API is dependent on R1 bit31. If it is set, the API is as above (and bit31 must be masked out). Otherwise it is as OS_ReadLine:
| Entry | |
|---|---|
| R0 | Buffer + flags |
| R1 | Size of buffer -1 |
| R2 | Lowest char allowed |
| R3 | Highest char allowed |
| R4 | Character to output (if bit 30 set) |
| Exit | |
|---|---|
| R0 | Buffer address, without flags |
| R1 | Chars read, excluding Return |
| R2 | Preserve |
| R3 | Preserve |
| R4 | Preserve |
| C flag is set if input is terminated by an escape condition | |
Use
This vector is called to indirect all calls to OS_ReadLine and OS_ReadLine32.
Notes
Claimants must first check the processor mode. If running in a 32bit mode, the OS_ReadLine32 API is used, with flags in R4. Else, if R1 bit31 is set, the OS_ReadLine32 API is used, with flags in R4. Otherwise, the OS_ReadLine API is used, with flags in R0.
As well as the kernel, common implementations can be found in the ReadLine and LineEditor third-party modules.
See also
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