Each Tcl interpreter object (i.e., the context that knows how to run a Tcl procedure) can only be safely used from the OS thread that creates it. This is because Tcl doesn’t use a global interpreter lock like Python, and instead makes extensive use of thread-specific data to reduce the number of locks required internally. … Read more
All Tcl commands need to originate from the same thread. Due to tkinter‘s dependence on Tcl, it’s generally necessary to make all tkinter gui statements originate from the same thread. The problem occurs because mainWindow is instantiated in the tkinterGui thread, but — because mainWindow is an attribute of tkinterGui — is not destroyed until … Read more
A general list for Bindings and Events can be found on effbot.org or in the docs provided by New Mexico Tech whereas the name of several keys are listed here in addition to the original documentation. Here’s a summary of the most common events with some keypress names explained: Event Description <Button-1> Button 1 is … Read more
Why is it considered bad to have multiple instances of Tk? Tkinter is just a python wrapper around an embedded Tcl interpreter that imports the Tk library. When you create a root window, you create an instance of a Tcl interpreter. Each Tcl interpreter is an isolated sandbox. An object in one sandbox cannot interact … Read more
To get the date-string in bash: echo “Current: ” $(date +”%Y”-“%m”-“%d”T”%H”-“%M”-“%S”) echo “+2 min : ” $(date –date=”@$(($(date +%s)+120))” +”%Y”-“%m”-“%d”T”%H”-“%M”-“%S”) prints Current: 2014-09-10T15-58-15 +2 min : 2014-09-10T16-00-15 Read the time from string and print +2min string str=”2014-09-10T15-58-15″ new=$(date –date=”@$(($( IFS=”-T” read y m d H M S <<< “$str”;date –date=”$y-$m-${d}T$H:$M:$S” +%s )+120))” +”%Y”-“%m”-“%d”T”%H”-“%M”-“%S”) echo “From … Read more
There are several problems with your script. The first of which is on the first line: set QA1 array() This doesn’t do what you think it does. What it does is create a scalar variable (not an array) that contains the seven character string “array()”. Later you try to access it as an array: set … Read more