Support for wider print-outs in DP4 - E4000035 - 19 Oct 2001

Until now DP4 programs have been restricted to a line length of 510 characters when creating file-output via forms. In particular Export programs created with Report Writer could not export large tables in a simple way. This restriction has been removed from DP4, and you can create files with line lengths of up to 9999 characters. However, it should be noted that, at least in 4.5xx, a single map cannot be wider than 250 characters, so that the output must be built up by output using the "form beside" technique, either in C or QAB. (In 4.6xx you can create much wider maps than this in principle, but the "form beside" technique is probably more practical even so). Report Writer uses a similar technique, so creating wide reports and exports should be straight-forward.

In order to enable wide output you must create a suitable Device Group and P.O.D. using DFSETUP (posting the map file included with the download will do this automatically). The Device Group should be set up to specify a suitably large page width - i.e. the maximum anticipated width you will need to use. Specifying an unecessarily high width will impact performance when printing using the device. In the new version of the DP4 terminal manager, the page width specified for a device is used to allocate print buffers, and attempting to create print out wider than the specified page width may cause output to be truncated. (The page width will normally be rounded up slightly from the specified value, and will always be at least 510, for compatibility with existing programs).

To create a wide Report or Export program using Report Writer you should do as follows:

• Use the new version of REPSETUP provided, and specify a command tail -maxwidth width where width is the desired maximum width. If you forget this command tail you will be restricted to 500 characters, except for fixed width Export programs. You must also specify this command tail later on if you want to tun the -test options against existing wide print-out programs. It is not very elegant to have to use this command tail, but unfortunately the logic of REPSETUP makes it difficult to avoid the need for it.
• In the Output Devices Dialogs in REPSETUP and REPPRINT make sure you specify the EXPORT_FILE device or another wide device you have set up.

One point to note, is that if you use the option in REPPRINT to suppress trailing spaces, your print device must be wide enough to cope with lines with no trailing spaces at all - all lines will be initially created like this, the spaces are only removed when the output file is finally written.

29 October 2001 The download has been updated to fix a bug with radio buttons introduced into 4.619

DP4 Version Compatibility

Beta software is supplied without warranty and should not be used in live sites without the agreement of Itim Technology Solutions. Compatibility with an eventual final release cannot be guaranteed.

Downloads

Beta Win32 4.620 components
This enhancement is also available for 4.523 Unix/Linux DP4.

To enable this enhancement proceed as follows:

1. Use MAPPOST to post the file containing map changes (system.m6), and the file containing the default wide device (widedvc.prn) to your system database:
   mappost -quiet system.m6 widedvc.prn

2. Copy your current system database to another name, such as sysnew, and run setsessn against it.

3. Post the system.db file contained in the download to this database using copydb as follows:
   copydb -db sysnew -post system.db -nodata -quiet

4. Run setsessn against the new database again and copy it back over your current system database.