eval really isn't reliable here. The program may very well start in X if X is running, even if it is not called under X.
 IMHO, you really should check for $ENV{DISPLAY}, if X is running and DISPLAY is not set it is really the user's problem, not yours.
 Some gui toolkits have their own internal checks for this stuff, gtk has something like init_check() (wondering if it can run or not) maybe you could find something similar in Tk. This seems too low-level though for whatever the gui toolkit not to have.
 But again, until then, use $ENV{DISPLAY}. If the user doesn't have it set and has X running, i can bet it wouldn't be just your application he would have problems with.

--
perl -MLWP::Simple -e'print$_%%\n|,<br> get(q=http://cpan.org/misc/japh=)))'

In reply to Re^3: How to detect X? by zgrim
in thread How to detect X? by blazar

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