To 'GUI' or Not to 'GUI'

If you have a mixed environment, with some users connecting with terminal emulation, and some with a GUI interface, it might be handy to be able to tell which interface is currently being used. Here are two techniques:

    * Are we character or are we GUI (Presentation Manager)?
    * A presentation manager session has '-f=' on its
    * command line (as viewed with 'ps -ef'). We can check for this
    * and if it's there, it means this session is using P/M or JAVA
    * client. If not, we are a normal character based session.
    SET     --- TEMP 80 = -f
    SET     --- LI = 80
    PASS    --- TEMP 80 FIELD SHARE? Y
    PASS    --- LI      FIELD SHARE? Y
    CALL    ,RT_GETPARAM RESIDENT? Y END? N FAIL 0
    * if TEMP 80 still contains '-f', then we are *not* P/M
    * if it contains anything else (usually 4, don't know why) then we
    * are GUI P/M or JAVA
    IF --- TEMP 80 EQ -f
T   SET --- TEMP 1 = C
F   SET --- TEMP 1 = G

The above technique also demonstrates the use of RT_GETPARAM to check for arguments on the command line. TEMP 80 contains the parameter we are interested in ('-f' in this case). After calling RT_GETPARAM, TEMP 80 will either contain the data on the right hand side of '-f=', or it will still contain '-f' if '-f' is not found on the command line. This approach does not distinguish between the Java Client and the Presentation Manager client.

Another approach is:

    PASS --- FEATURE TOKEN SCANLIST FIELD SHARE? Y
    CALL ,RT_CHECK_CLI_FEATURE RESIDENT? N END? N FAIL 0
    IF --- RETURN CODE EQ +1
T   It's the Java Client
F   It's not

This technique specifically tests for the Java client, and will return +0 if the user is character or Presentation Manager.





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