[Info-vax] disabling a CTRL/Y ast

[Bob Gezelter]

On Wednesday, January 6, 2016 at 10:15:11 AM UTC-5, Tom Adams wrote:
> Section 5.4.3.2 here:
> 
> http://www2.hmc.edu/www_common/OVMS072-OLD/72final/6136/6136pro_019.html
> 
> explains how to enable a ctrl/y ast using IO$M_CTRLYAST. It also says:
> 
> "This function code is also used to disable the AST."
> 
> but I cannot figure out the arguments of the QIOW call that would disable the AST.
> 
> How does one disable the AST?

Tom,

>From the referenced page:

"5.4.3.2 Enable Ctrl/C AST and Enable Ctrl/Y AST Function Modifiers

Both set mode functions can take the enable Ctrl/C AST and enable Ctrl/Y AST function modifiers. These function modifiers request the terminal driver to queue an AST for the requesting process when you press Ctrl/C or Ctrl/Y. The following combinations of function code and modifier are provided:

    IO$_SETMODE!IO$M_CTRLCAST---Enable Ctrl/C AST
    IO$_SETMODE!IO$M_CTRLYAST---Enable Ctrl/Y AST 

These function code modifier pairs take the following device- or function-dependent arguments:

    P1---Address of the AST service or 0 if the corresponding AST is disabled
    P2---AST parameter
    P3---Access mode to deliver AST (maximized with caller's access mode)"

Note the description of P1, to wit: "... 0 if the corresponding AST is disabled". Admittedly, the English could be better ("is disabled" would probably be better described as "is to be disabled.").

- Bob Gezelter, http://www.rlgsc.com