Name
bgexec
- bgexec
varName
[options
...]command
[arg arg
...] Run an external program, like the Tcl exec command, but allow Tk to process events while the program is running.
Parameter
varName
is a global variable that will be set to the program’s exit status when the command is completed. Setting the variable will cause the pr ogram to be terminated with a signal.Parameters
command
andarg
s specify an external command with optional arguments in the same form as accepted by the Tcl exec command.Normally, bgexec returns the results of the program. However, if the last argument is the ampersand (&), bgexec immediately returns a list of the spawned pr ocess IDs. The variable
varName
can be used with the tkwait command to wait for the program to finish.
Options
- -error
varName
Cause
varName
to be set to the contents of standard error when the command has completed.- -update
varName
Cause
varName
to be set whenever data is written to standard output by the command.- -keepnewline
boolean
Enable or disable truncation of newline from last line of output.
- -killsignal
signal
Specify (by name or number) the signal to be sent to the command when terminating. The default signal is SIGKILL.
- -lasterror
varName
Same as the -error option, except
varName
is updated as soon as new data is available.- -lastoutput
varName
Same as the -output option, except
varName
is updated as soon as new data is available.- -onerror
cmdPrefix
When new data from standard error is available, evaluate the command
cmdPrefix
with the new data ...
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