Re: 4GL RUN command question

Candy McCall wrote: Billy Wheeler asked for someone more awake. Here goes... ZZZzzzz... > > Within a 4GL program, I want to run a shell > script which will calculate an integer value. > I then want to read that integer value into > the 4GL program. Is it possible to > read that value using the "RUN shell_script RETURNING > integer_variable" command? The shell will return its status to 4GL (see manual). It does this with the parameter to the exit command. As Billy says, it can be 0 to 255, with 0 by convention meaning OK and the rest an error in the shell script. > > I've also thought of setting a value in a shell > environment variable in the shell script and > then reading the value using fgl_getenv(), but since > the shell_script is a child process, I didn't think I could > set a shell environment variable of the parent process > (the 4GL program). Correct. A moment's thought will reveal the awful security risk if you could do this. > > A third way I've thought of is to place the integer variable > in an ASCII file, then using the LOAD command, load > the value into a temporary table. This is not the most > elegant way of getting that value, but it will work. > Does anyway know of a better way? Not elegant and not quick, as you will need two database connections. You could write to a file in the shell and then read (or load) that from the 4GL caller - only one connection. There are file-reading functions in the IIUG archives. > > Thanks in advance, > Candy > -- > Candy McCall > ONLINE Computing, Inc. > (candym@olcinc.com) Returning to the beginning, why do you want to do this? Calling a shell script from 4GL just to do some sums seems strange. Is there some other way? If you want a general expression evaluation, there has been some discussion of that recently - see the usual dejanews. It occurs to me that you could embed a tcl interpreter into your 4GL program. Don't ask me how it's done, I just have a feeling that's what tcl was designed for. Anyone else know more than I do (silly question)? -- Peter Lancashire Information Systems Specialist, Bayer plc Eastern Way, Bury St Edmunds, Suffolk, IP32 7AH, UK Tel: +44-1635-562258, Fax: +44-1635-562281 --- If all else fails, read the instructions and the release notes. Join Infuse, the UK Informix User Group at http://www.infuse.org.uk/ ---