Initial Check-in

DemoPrograms/Demo_Script_Launcher_Realtime_Output.py

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+import subprocess
+import sys
+import PySimpleGUI as sg
+
+"""
+    Demo Program - Realtime output of a shell command in the window
+        Shows how you can run a long-running subprocess and have the output
+        be displayed in realtime in the window.
+"""
+
+def main():
+    layout = [  [sg.Text('Enter the command you wish to run')],
+                [sg.Input(key='_IN_')],
+                [sg.Output(size=(60,15))],
+                [sg.Button('Run'), sg.Button('Exit')] ]
+
+    window = sg.Window('Realtime Shell Command Output', layout)
+
+    while True:             # Event Loop
+        event, values = window.Read()
+        # print(event, values)
+        if event in (None, 'Exit'):
+            break
+        elif event == 'Run':
+            runCommand(cmd=values['_IN_'], window=window)
+    window.Close()
+
+
+def runCommand(cmd, timeout=None, window=None):
+    """ run shell command
+	@param cmd: command to execute
+	@param timeout: timeout for command execution
+	@param window: the PySimpleGUI window that the output is going to (needed to do refresh on)
+	@return: (return code from command, command output)
+	"""
+    p = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+    output = ''
+    for line in p.stdout:
+        line = line.decode(errors='replace' if (sys.version_info) < (3, 5) else 'backslashreplace').rstrip()
+        output += line
+        print(line)
+        window.Refresh() if window else None        # yes, a 1-line if, so shoot me
+
+    retval = p.wait(timeout)
+    return (retval, output)
+
+
+main()