November 1999
Intermediate to advanced
832 pages
19h 28m
English
Content preview from Practical Programming in Tcl & Tk, Third Edition
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Hidden Commands
The commands listed in Table 19-2 are hidden instead of being completely removed. A hidden command can be invoked in a slave by its master. For example, a master can load Tcl scripts into a slave by using its hidden source command:
interp create -safe slave interp invokehidden slave source filename
Without hidden commands, the master has to do a bit more work to achieve the same thing. It must open and read the file and eval the contents of the file in the slave. File operations are described in Chapter 9.
interp create -safe slave set in [open filename] interp eval slave [read $in] close $in
Hidden commands were added in Tcl 7.7 in order to better support the Tcl/Tk browser plug-in described in Chapter 20. In some cases, ...
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