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The CICA Windows Explosion!
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The CICA Windows Explosion! - Disc 2.iso
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demo
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wit472.zip
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DEMO
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DEADLOCK.HLP
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DEADLOCK.bin
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1994-11-25
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22 lines
IGRAPH
deadlock --- example of dataflow deadlock
DESCRIPTION
The deadlock igraph illustrates an incorrectly designed dataflow
graph. The intent of this graph is to overlay a logo image on a series
of images picked out by the dir operator. A sequencer is used to submit
each element of a vector of filenames received by the dir operator to
it's rdObj operator. The rdObj operator will read the image with the
filename received by the sequencer. The image is sent to the aluOp where
it is overlayed with the logo image read by the second rdObj operator.
As the sequencer can generate many objects from its input vector,
the rdObj and aluOp operators connected to the output of the sequencer
may execute many times. The logo image, however, is only read once but
is used each time the sequencer fires an output. In fact, the second time
the logo image is required by the aluOp, the igraph will stop since the
aluOp lacks the logo image input. See deadlockFixed to repair this
problem.