• shellExec ?-outProc proc? ?-errProc proc? ?-stopProc proc? ?-timeout num? ?-success val? ?-preserve? ?--? scriptPath ?argList?
Execute a shell command synchronously. The scriptPath argument is the full path of the shell script to execute. This path may contain shell symbols like .. or ~. The argList argument is a Tcl list containing the arguments to pass to the shell command.
The -outProc and -errProc options specify Tcl callbacks which will be invoked each time new data is received on the stdout or stderr channels of the shell command respectively. If only -outProc is specified, then the -errProc option is automatically set to the same value. These callbacks are Tcl procs accepting a single argument which represents the received data. The callbacks are optional: if they are not specified, the shellExec command returns the entire output of the executed shell command upon completion.
The -timeout specifies a timeout in seconds. If the elapsed time since the shell command was launched exceeds the timeout, the shell command will receive an interrupt signal. By default, there is no timeout.
The -stopProc option specifies a Tcl proc which is invoked periodically to ask whether the execution should be interrupted. This proc takes no argument and should return 1 to interrupt the execution, or 0 otherwise.
By default, the command succeeds if the shell command terminates with a 0 status (which is usual practice with shell commands). The -success option can be used to specify another value for successful termination. If the termination status differs from the expected success value, the shellExec command raises an error.
The '--' switch indicates the end of the shellExec command's options.
The -preserve option is very technical. Normally, the system applies a Unicode formD decomposition to all the arguments contained in argList. For some command line tools, this can be undesirable. The -preserve option tells the command to keep the arguments verbatim, that is, to pass them as they are, without decomposing.