[Info-vax] disabling a CTRL/Y ast

[Tom Adams]

On Wednesday, January 6, 2016 at 10:54:22 AM UTC-5, Stephen Hoffman wrote:
> On 2016-01-06 15:15:09 +0000, Tom Adams said:
> 
> > 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$M_CTRLYAST. It also says:
> > 
> > "This function code is also used to disable the AST."
> > 
> > but I cannot figure out the arguments of the QIOW call that would 
> > disable the AST.
> > 
> > How does one disable the AST?
> 
> 
> That doesn't do what you want.
> 
> That disables the AST that was set -- by specifying 0 as the AST routine 
> address -- but in the case you're still working toward, you want no ^Y.
> 
> "P1---Address of the AST service or 0 if the corresponding AST is disabled"
> 
> See the lib$enable_ctrl and lib$disable_ctrl calls to enable and 
> disable the associated CLI-level handling -- which is what you want and 
> need here, if you're not going to segment the code to avoid the problem 
> -- and also see replies to your previous postings here.
> 
> 
> 
> -- 
> Pure Personal Opinion | HoffmanLabs LLC

I want to turn ctrl/y into a noop in certain regions of code and turn ctrl/y into an exit in other regions of code.

I do find that it is necessary to run lib$disable_ctrl at the beginning of the program and lib$enable_ctrl at the end of the program to restore the previous CLI state, but I need to run asts to do the rest.