avoid needless list construction

[lilass.git] / dsl.py

diff --git a/dsl.py b/dsl.py
index b4f77bf413391f2bf4b7e01d835c80b76b695299..7dc86654ec88bb6066cf073050bf5d68104192e0 100755 (executable)
--- a/dsl.py
+++ b/dsl.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/python3
 # DSL - easy Display Setup for Laptops
 # Copyright (C) 2012 Ralf Jung <post@ralfj.de>
 #
@@ -57,15 +57,15 @@ class ScreenSetup:
                return args
 
 # Load a section-less config file: maps parameter names to space-separated lists of strings (with shell quotation)
-def loadConfigFile(file):
+def loadConfigFile(filename):
        import shlex
        result = {}
-       if not os.path.exists(file):
+       if not os.path.exists(filename):
                return result # no config file
        # read config file
        linenr = 0
-       with open(file) as file:
-               for line in file:
+       with open(filename) as f:
+               for line in f:
                        linenr += 1
                        line = line.strip()
                        if not len(line) or line.startswith("#"): continue # skip empty and comment lines
@@ -82,10 +82,9 @@ def loadConfigFile(file):
 # helper function: execute a process, return output as iterator, throw exception if there was an error
 # you *must* iterate to the end if you use this!
 def processOutputGen(*args):
-       p = subprocess.Popen(args, stdout=subprocess.PIPE)
-       for line in p.stdout:
-               yield line
-       p.wait() # wait for process to exit (it closed stdout, so it can't block anymore)
+       with subprocess.Popen(args, stdout=subprocess.PIPE) as p:
+               for line in p.stdout:
+                       yield line.decode("utf-8")
        if p.returncode != 0:
                raise Exception("Error executing "+str(args))
 def processOutputIt(*args):
@@ -118,7 +117,7 @@ def getXrandrInformation():
                # unknown line
                # not fatal as my xrandr shows strange stuff when a display is enabled, but not connected
                #raise Exception("Unknown line in xrandr output:\n"+line)
-               print "Warning: Unknown xrandr line %s" % line
+               print("Warning: Unknown xrandr line %s" % line)
        return connectors
 
 # convert a (width, height) pair into a string accepted by xrandr as argument for --mode
@@ -171,7 +170,7 @@ def classifyConnectors(allConnectors):
                        if connector == internalConnector:
                                raise Exception("%s is both internal and external, that doesn't make sense." % connector)
        else:
-               externalConnectors = allConnectors.keys()
+               externalConnectors = list(allConnectors.keys())
                externalConnectors.remove(internalConnector)
        if not externalConnectors:
                raise Exception("No external connector found - either your config is wrong, or your machine has only one connector.")
@@ -232,7 +231,7 @@ if __name__ == "__main__":
                call = ["xrandr"]
                for name in connectorArgs:
                        call += ["--output", name] + connectorArgs[name]
-               print "Call that will be made:",call
+               print("Call that will be made:",call)
                subprocess.check_call(call)
        except Exception as e:
                frontend.error(str(e))