The ImageViewer (sdtimage) can freeze in limited circumstances during the manipulation of an image on a screen. This problem only occurs when XIL is using the X Shared Memory (xshm) display pipeline. A thread deadlock may be the cause of the problem between XIL and xshm.
The xshm pipeline is only used when the workstation framebuffer does not have an accelerated XIL display driver available, such as the TCX and ZX framebuffers. Existing accelerated XIL drivers for cg6(GX), cg14(SX), ffb(Creator) and afb(Elite) framebuffers do not cause this problem.
Workaround: If this problem occurs, use the Image Tool (/usr/openwin/bin/imagetool) as a substitute for sdtimage.