While I was writing that previous blog about handling wide fat screens I stumbled across another useful API (QSNRTVMOD) for retrieving the current screen mode that we are displaying. This means we could find our screen width programmatically. Why isnt that a word?
I’m not too sure why anyone would want to do this but… in the spirit of sharing stuff on the same theme as the widescreen gubbins I was mumbling about earlier…
We can find out if we are displaying a 24×80 or a 27×132 screen with this little gem:
QSNRTVMOD
The QueueueuSinnerTeevumMod API will return a code and tell us what screen format we are using in our 5250 session.
We can add some error handling to the RPG program without changing any DDS in our *DSPF..
Procedure – Retrieve the Screen Mode
// +------------------------------------------------------------------+
// | Procedure to retrieve current screen mode ('3'=24x80 '4'=27x132) |
// +------------------------------------------------------------------+
dcl-proc #RtvScrnMode export;
dcl-pi #RtvScrnMode char(1) end-pi;
dcl-s currentScrnSize char(1) inz('0');
dcl-ds myApiError inz qualified;
Bytes int(10) inz( %size( myApierror ));
BytesAvailable int(10) inz;
ErrorID char(7) inz;
Reserved char(1) inz( x'00' );
MessageData char(128) inz;
end-ds;
dcl-pr QsnRtvMod extproc( 'QsnRtvMod' );
*n char(1); // DspMode
*n int(10) options( *omit ); // Handle
*n options( *omit: *varsize ) like( myApierror ); // ErrorDS
end-pr;
QsnRtvMod ( currentScrnSize
: *Omit
: *Omit
);
// Too lazy to add error handling for 'myApiError' but you could do that here
Return currentScrnSize;
end-proc;
(obviously this code should be in a service program to make it reusable but for code readability in this blog I’ve copy/pasted it separately)
Mainline – Check screen size before doing something
So, now we just need to check our screen size before doing something.
I’m not too sure if this is ever helpful technique really… I mean I have never had to use it in anger… but that doesnt mean that somebody out there might be looking for exactly this solution 🙂
// Procedure to retrieve current screen mode (3=24x80; 4=27x132) If RtvScreenMode() = '3'; // do some stuff for 24x80 screens If RtvScreenMode() = '4'; // do some stuff for 27x132 screens else; // do some error handling stuff or perhaps handle totally weird screen sizes endif; *inlr = *on;
NOTE: This API is telling you the last screen size displayed not the screen size that the 2520 terminal is capable of. In other words – if you are logged into a 27×132 terminal but displaying a 24×80 screen and run this code it will tell you its 24×80. Go to a main IBM i menu like (GO MAIN) and it will say it’s 24×80 but call it from a widescreen format (like SEU-WIDE for example) and it will tell you it’s 27×132
Comprendez?
