Written November 2025
A-Shell supports several mechanisms for obtaining keyboard, file or socket input, summarized below. Note that the apparent overlap between some of the mechanisms, particularly the single character XCALLs, is a historical artifact related to supporting third-party developers migrating to A-Shell. Also note due to the ease of creating external SBX subroutines, it's common for developers to create their own custom input routines that wrap one or more of the common routines below.
Mechanism |
Data Source |
ASB Category |
Description |
GUI* Support? |
|---|---|---|---|---|
Keyboard or File |
Statement |
Line, raw, fields, CSV |
|
|
Keyboard |
Function |
Single character, test for availability |
|
|
Keyboard |
Xcall |
Single character if available |
|
|
Keyboard |
Xcall |
Single character, wait |
|
|
Keyboard |
Xcall |
Same as ACCEPT but without echo |
Yes |
|
Keyboard or File |
Xcall |
1 to n characters, timeout option |
|
|
Socket |
Xcall |
General TCP input/output |
n/a |
|
Random or ISAM file |
Statement |
Record-oriented input |
n/a |
|
Random or ISAM file |
Statement |
Variation of READ |
n/a |
|
File |
Xcall |
Simplified version of GET |
|
|
Keyboard |
Xcall |
Sophisticated single-field input; text or GUI |
Yes |
|
Keyboard |
SBX |
Extended GUI wrapper for INFLD |
Yes |
|
Keyboard |
Xcall |
Multi line text, pick lists, menus |
Yes |
|
Keyboard |
Xcall |
Embedded word processor (GUI) |
Yes |
|
Keyboard |
Xcall |
Grid-style display and input |
Yes |
|
Keyboard |
Xcall |
Edit box and other Windows controls |
Yes |
|
ISAM-A file |
Statement |
Indexed record input |
|
|
Keyboard |
Xcall |
Same as ACCEPN but with function key support |
Yes |
| * | GUI support indicates that the mechanism has explicit support for GUI—it is able to create a GUI control to perform the function. Note however that the single character input routines, particularly without echo, are perfectly functional in a GUI environment since they don't affect the display. |
