File fix-python3-and-unbuffered-io.patch of Package irqstat

commit 949d40b8d5c8bb78bb229d96c4b62122b66c4839
Author: Dario Faggioli <dfaggioli@suse.com>
Date:   Tue Mar 23 16:01:15 2021 +0000

    Workaround Python 3 not doing unbuffered IO for text files
    
    On python3, running with -b cause this:
    
    Traceback (most recent call last):
      File "/usr/bin/irqstat", line 401, in <module>
        sys.exit(main(sys.argv))
      File "/usr/bin/irqstat", line 385, in main
        sys.stdout = os.fdopen(sys.stdout.fileno(), 'w', 0)
      File "/usr/lib64/python3.8/os.py", line 1023, in fdopen
        return io.open(fd, *args, **kwargs)
    ValueError: can't have unbuffered text I/O
    
    That's because unbuffered IO can't be done any longer
    (unless for binary IO).
    
    Workaround that wrapping stdout in a stream that is always
    flushed.
    
    Signed-off-by: Dario Faggioli <dfaggioli@suse.com>

diff --git a/irqstat b/irqstat
index fe882f4..9183a5a 100755
--- a/irqstat
+++ b/irqstat
@@ -45,6 +45,17 @@ try:
 except ImportError:
     import _thread as thread
 
+class Unbuffered:
+    def __init__(self, stream):
+        self.stream = stream
+    def write(self, data):
+        self.stream.write(data)
+        self.stream.flush()
+    def writelines(self, datas):
+        self.stream.writelines(datas)
+        self.stream.flush()
+    def __getattr__(self, attr):
+        return getattr(self.stream, attr)
 
 KEYEVENT = threading.Event()
 
@@ -382,7 +393,7 @@ def main(args):
         # input thread
         thread.start_new_thread(wait_for_input, tuple())
     else:
-        sys.stdout = os.fdopen(sys.stdout.fileno(), 'w', 0)
+        sys.stdout = Unbuffered(sys.stdout)
 
     try:
         display_itop(options.batch, int(options.time), int(options.rows),