There are up to 128 user function keys. The defaults supplied with your COBOL system differ on different operating environments, but some keys are standard.
| Keystroke | User Function Key Number | 
|---|---|
| Escape | 0 | 
| F1 | 1 | 
| F2 | 2 | 
| F3 | 3 | 
| F4 | 4 | 
| F5 | 5 | 
| F6 | 6 | 
| F7 | 7 | 
| F8 | 8 | 
| F9 | 9 | 
| F10 | 10 | 
Your keyboard might not have these keys, but if they are there, they should be configured as above. Additionally, the following user function keys might be defined:
| Keystroke | User Function Key Number | 
|---|---|
| Shift+F1 - Shift+F10 | 11 - 20 | 
| Ctrl+F1 - Ctrl+F10 | 21 - 30 | 
| Alt+F1 - Alt+F10 | 31 - 40 | 
| Alt+1 - Alt+9 | 41 - 49 | 
| Alt+0 | 50 | 
| Alt+- | 51 | 
| Alt+= | 52 | 
| PgUp | 53 | 
| PgDn | 54 | 
| Ctrl+PgUp | 55 | 
| Ctrl+PgDn | 56 | 
| Alt+A - Alt+Z | 65 - 90 | 
| F11 | 91 | 
| F12 | 92 | 
| Shift+F11 | 93 | 
| Shift+F12 | 94 | 
| Ctrl+F11 | 95 | 
| Ctrl+F12 | 96 | 
| Alt+F11 | 97 | 
| Alt+F12 | 98 |