[issue44415] sys.stdout.flush and print() hanging
New submission from Rajeev Chaurasia :
I am running an application using cronjob. This application runs on
Linux(X86_64) platform where inside a loop we have print() and
sys.stdout.flush() statements. This loop iterates around 500 times and after
the loop we have few more sys.stdout.flush() and print() statements.
When I am running same application on terminal (without cronjob) then it is
working fine.
Inside the loop everything is working fine but application is hanging after the
loop. I put some debug statements and I found it is hanging on print() and
sys.stdout.flush().
Code logic:-
for x in range(500):
print(x)
print ("something")
sys.stdout.flush()
self.logger.info("A")
sys.stdout.flush() #1
self.logger.info("B")
print ("Hello")#2
self.logger.info("C")
print ("Bye") #3
self.logger.info("D")
-
"A" is getting printed in log file and nothing after that but-
If I comment #1 then I get "B" as well in the log file.
If I comment #2 then I get "C" as well in the log file
If I comment #3 then I get "D" as well in the log file.
-
ps results-
[root@scao05adm07 ~]# ps -ef|grep exachk
root 239265 98963 0 Jun11 ?00:00:00 sh /opt/oracle.ahf/bin/exachk
-silentforce -showpass -dball -nocvu -autorun_id DEFAULT
root 239706 239265 0 Jun11 ?00:00:35
/opt/oracle.ahf/python/bin/python /opt/oracle.ahf/exachk/exachk.py -silentforce
-showpass -dball -nocvu -autorun_id DEFAULT
root 277938 239706 0 Jun11 ?00:00:00 sh
/opt/oracle.ahf/exachk/exachk -silentforce -showpass -dball -nocvu -autorun_id
DEFAULT -localonly -sudo_remoterun 0
root 278989 277938 0 Jun11 ?00:12:26
/opt/oracle.ahf/python/bin/python /opt/oracle.ahf/exachk/exachk.py -silentforce
-showpass -dball -nocvu -autorun_id DEFAULT -localonly -sudo_remoterun 0
root 281983 278989 0 Jun11 ?00:00:27
/opt/oracle.ahf/python/bin/python /opt/oracle.ahf/exachk/exachk.py -silentforce
-showpass -dball -nocvu -autorun_id DEFAULT -localonly -sudo_remoterun 0
-
# uname -a
Linux 4.14.35-1902.306.2.2.el7uek.x86_64 #2 SMP Thu Nov 19
18:09:09 PST 2020 x86_64 x86_64 x86_64 GNU/Linux
-
I believe this issue is related to standard output buffer but I am not able to
find a fix for it.
Please help.
-Rajeev
--
components: Library (Lib)
messages: 395772
nosy: rajeevkchaurasia
priority: normal
severity: normal
status: open
title: sys.stdout.flush and print() hanging
versions: Python 3.8
___
Python tracker
<https://bugs.python.org/issue44415>
___
___
Python-bugs-list mailing list
Unsubscribe:
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44415] sys.stdout.flush and print() hanging
Rajeev Chaurasia added the comment:
self.logger = lib.logger.Log()
We have cronjob entry to call the application everyday
$crontab -e
0 1 * * * /scratch/rajeev/cronjob/exachk.sh
exachk.sh makes call to my python application as-
python3 /opt/oracle.ahf/exachk/exachk.py
Yes I am redirecting stdout to-
sys.stdout = lib.debugger.Tee("/tmp/exachk_screen_output_061321_23211.log")
I am not redirecting stderr anywhere.
--
___
Python tracker
<https://bugs.python.org/issue44415>
___
___
Python-bugs-list mailing list
Unsubscribe:
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44415] sys.stdout.flush and print() hanging
Rajeev Chaurasia added the comment: Thanks a lot Serhiy. Your suggested fix resolved the issue. -Rajeev -- stage: -> resolved status: open -> closed ___ Python tracker <https://bugs.python.org/issue44415> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue44433] processes created by subprocess.Popen is not terminating
New submission from Rajeev Chaurasia : I am using Linux OS and using multiprocessing in my application. The child process execution get completed but the processes are not terminating. childprocess = "/opt/oracle.ahf/exachk/exachk -silentforce -showpass -dball -nocvu -autorun_id DEFAULT -localonly -sudo_remoterun 0" session = subprocess.Popen(childprocess, shell = True) session.communicate() >From the log I can see execution of childprocess scripts(exachk and exachk.py) >is completed successfully but the process remains alive forever. Also the >parent process from where I am using subprocess.Popen that also remains alive. # ps -ef|grep exachk (P1) 278988 247699 0 18:46 ?00:00:00 sh /opt/oracle.ahf/exachk/exachk -silentforce -showpass -dball -nocvu -autorun_id DEFAULT -localonly -sudo_remoterun 0 (P2) 279873 278988 39 18:46 ?00:12:51 /opt/oracle.ahf/python/bin/python /opt/oracle.ahf/exachk/exachk.py -silentforce -showpass -dball -nocvu -autorun_id DEFAULT -localonly Please help! -Rajeev -- components: Library (Lib) messages: 395909 nosy: rajeevkchaurasia priority: normal severity: normal status: open title: processes created by subprocess.Popen is not terminating versions: Python 3.8 ___ Python tracker <https://bugs.python.org/issue44433> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
