argv@turnpike.Eng.Sun.COM (Dan Heller) (08/12/90)
Perhaps someone from osf and can answer this:
When you set the text widget's "value", you don't need to keep
around it's memory any longer, do you? I'm reasonably sure
it copies it into internal data space, but I can't find anywhere
in the source that does it. I do see places where it's copied
into _temporary_ internal buffers but not into permanent space.
The example programs that set the text's value use allocated
space and they never free it, but:
1) they never get the previous text and free it before assigning
the new text -- does XmText do that automatically?
2) I tried freeing the text immediately after setting the text's
value and it works fine in many programs. I haven't seen a
problem. Does this mean that my assumption is right that
the XmText widget copies and manages its own text?
--
dan
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O'Reilly && Associates argv@sun.com / argv@ora.com
Opinions expressed reflect those of the author only.carl@quad1.quad.com (Carl Priddy) (08/15/90)
From postnews Tue Aug 14 11:27:10 1990 In article <140523@sun.Eng.Sun.COM>, argv@turnpike.Eng.Sun.COM (Dan Heller) writes: > Perhaps someone from osf and can answer this: > When you set the text widget's "value", you don't need to keep > around it's memory any longer, do you? Dan, No you do NOT need to keep it around any longer. I believe, although I am not sure and have no hope of finding it documented anywhere, that all widgets that have string resources make copies of those strings. I too have experienced no problems after free'ing up the memory that contained them after I have set the values in the widgets. As to whether or not the widgets do the appropriate alloc and frees, one can only hope. I notice that you are from O'Reilly & Co. I am counting on you guys to provide relief for the Motif documentation vacuum. Good luck. carl.
mayer@hplabsz.HPL.HP.COM (Niels Mayer) (08/17/90)
In article <14342@gouda.quad.com> carl@quad1.quad.com (Carl Priddy) writes: >No you do NOT need to keep it around any longer. I believe, although I am not >sure and have no hope of finding it documented anywhere, that all widgets that >have string resources make copies of those strings. I too have experienced no >problems after free'ing up the memory that contained them after I have set >the values in the widgets. In theory, what you said is supposedly true. But.... in Motif 1.0, if you set XmNargv on an applicationShellWidgetClass instance to a recently malloc()'d argv and do XtFree(argv_copy) right after doing XtAppCreateShell(), you get a guaranteed core dump. If you free after doing XtRealizeWidget(), you don't.... >As to whether or not the widgets do the appropriate alloc and frees, one can >only hope. Leaks? What leaks? -- Niels "canary in a coal mine" Mayer.