Python Popen, OS, Commands all return nothing when running a command in linux
So I need to get the version of something on a client and when I try to use Popen, Call, Check_Call, OS, Commands it all returns a value of nothing. When I run the script on a system in putty it returns me an empty line. Can it be because of putty?. Running on Linux, CentOS if that makes any difference. Thank you guys ahead of time.
def getJavacVer():
p = sp.Popen("javac -version", stdout=sp.PIPE, shell=True)
(output, err) = p.communicate()
print output
python python-2.7 subprocess
asked Nov 13 '18 at 1:19
SomeSimpletonSomeSimpleton
84
add a comment |
So I need to get the version of something on a client and when I try to use Popen, Call, Check_Call, OS, Commands it all returns a value of nothing. When I run the script on a system in putty it returns me an empty line. Can it be because of putty?. Running on Linux, CentOS if that makes any difference. Thank you guys ahead of time.
def getJavacVer():
p = sp.Popen("javac -version", stdout=sp.PIPE, shell=True)
(output, err) = p.communicate()
print output
python python-2.7 subprocess
asked Nov 13 '18 at 1:19
SomeSimpletonSomeSimpleton
84
Possible solution might be giving complete path for "javac". Also, PIPE stderr as well and check it. You might find something there
– Shriroop Joshi
Nov 13 '18 at 1:30
add a comment |
So I need to get the version of something on a client and when I try to use Popen, Call, Check_Call, OS, Commands it all returns a value of nothing. When I run the script on a system in putty it returns me an empty line. Can it be because of putty?. Running on Linux, CentOS if that makes any difference. Thank you guys ahead of time.
def getJavacVer():
p = sp.Popen("javac -version", stdout=sp.PIPE, shell=True)
(output, err) = p.communicate()
print output
python python-2.7 subprocess
asked Nov 13 '18 at 1:19
SomeSimpletonSomeSimpleton
84
So I need to get the version of something on a client and when I try to use Popen, Call, Check_Call, OS, Commands it all returns a value of nothing. When I run the script on a system in putty it returns me an empty line. Can it be because of putty?. Running on Linux, CentOS if that makes any difference. Thank you guys ahead of time.
def getJavacVer():
p = sp.Popen("javac -version", stdout=sp.PIPE, shell=True)
(output, err) = p.communicate()
print output
python python-2.7 subprocess
python python-2.7 subprocess
asked Nov 13 '18 at 1:19
SomeSimpletonSomeSimpleton
84
asked Nov 13 '18 at 1:19
SomeSimpletonSomeSimpleton
84
asked Nov 13 '18 at 1:19
SomeSimpletonSomeSimpleton
84
asked Nov 13 '18 at 1:19
SomeSimpletonSomeSimpleton
84
asked Nov 13 '18 at 1:19
SomeSimpletonSomeSimpleton
84
84
Possible solution might be giving complete path for "javac". Also, PIPE stderr as well and check it. You might find something there
– Shriroop Joshi
Nov 13 '18 at 1:30
add a comment |
Possible solution might be giving complete path for "javac". Also, PIPE stderr as well and check it. You might find something there
– Shriroop Joshi
Nov 13 '18 at 1:30
Possible solution might be giving complete path for "javac". Also, PIPE stderr as well and check it. You might find something there
– Shriroop Joshi
Nov 13 '18 at 1:30
Possible solution might be giving complete path for "javac". Also, PIPE stderr as well and check it. You might find something there
– Shriroop Joshi
Nov 13 '18 at 1:30
add a comment |
3 Answers
3
active
oldest
votes
The javac program returns the -version output through stderr, so stderr argument of Popen also need to be passed. Try:
>>> from subprocess import Popen
>>> from subprocess import PIPE
>>> p = Popen(['javac', '-version'], stdout=PIPE, stderr=PIPE)
>>> p.communicate()
(b'', b'javac 1.8.0_171n')
The second element is of the result is the captured output of the stderr stream, which contains the version number.
answered Nov 13 '18 at 1:32
metatoastermetatoaster
9,76212640
Wow okay, this is very interesting. Thank you for awnsering my question. I have a secondary question is there any reason for it returning it to stderr?
– SomeSimpleton
Nov 13 '18 at 1:36
The developers behind it might think that those particular output don't belong to the standard stream - however, these kind of decisions are up to whoever that wrote the program so you will have to ask them.
– metatoaster
Nov 13 '18 at 1:47
add a comment |
This will only work on *nix:
import commands
print commands.getstatusoutput('javac -version')
answered Nov 13 '18 at 1:22
Madison CourtoMadison Courto
424212
Okay this one worked. Thank you
– SomeSimpleton
Nov 13 '18 at 1:34
Would you mind marking as answered please
– Madison Courto
Dec 24 '18 at 17:41
add a comment |
Thank you to the few fellas that answered the question. The output is being put out to stderr instead of stdout. Thank you to everyone
answered Nov 13 '18 at 17:37
SomeSimpletonSomeSimpleton
84
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
The javac program returns the -version output through stderr, so stderr argument of Popen also need to be passed. Try:
>>> from subprocess import Popen
>>> from subprocess import PIPE
>>> p = Popen(['javac', '-version'], stdout=PIPE, stderr=PIPE)
>>> p.communicate()
(b'', b'javac 1.8.0_171n')
The second element is of the result is the captured output of the stderr stream, which contains the version number.
answered Nov 13 '18 at 1:32
metatoastermetatoaster
9,76212640
Wow okay, this is very interesting. Thank you for awnsering my question. I have a secondary question is there any reason for it returning it to stderr?
– SomeSimpleton
Nov 13 '18 at 1:36
The developers behind it might think that those particular output don't belong to the standard stream - however, these kind of decisions are up to whoever that wrote the program so you will have to ask them.
– metatoaster
Nov 13 '18 at 1:47
add a comment |
The javac program returns the -version output through stderr, so stderr argument of Popen also need to be passed. Try:
>>> from subprocess import Popen
>>> from subprocess import PIPE
>>> p = Popen(['javac', '-version'], stdout=PIPE, stderr=PIPE)
>>> p.communicate()
(b'', b'javac 1.8.0_171n')
The second element is of the result is the captured output of the stderr stream, which contains the version number.
answered Nov 13 '18 at 1:32
metatoastermetatoaster
9,76212640
Wow okay, this is very interesting. Thank you for awnsering my question. I have a secondary question is there any reason for it returning it to stderr?
– SomeSimpleton
Nov 13 '18 at 1:36
The developers behind it might think that those particular output don't belong to the standard stream - however, these kind of decisions are up to whoever that wrote the program so you will have to ask them.
– metatoaster
Nov 13 '18 at 1:47
add a comment |
The javac program returns the -version output through stderr, so stderr argument of Popen also need to be passed. Try:
>>> from subprocess import Popen
>>> from subprocess import PIPE
>>> p = Popen(['javac', '-version'], stdout=PIPE, stderr=PIPE)
>>> p.communicate()
(b'', b'javac 1.8.0_171n')
The second element is of the result is the captured output of the stderr stream, which contains the version number.
answered Nov 13 '18 at 1:32
metatoastermetatoaster
9,76212640
The javac program returns the -version output through stderr, so stderr argument of Popen also need to be passed. Try:
>>> from subprocess import Popen
>>> from subprocess import PIPE
>>> p = Popen(['javac', '-version'], stdout=PIPE, stderr=PIPE)
>>> p.communicate()
(b'', b'javac 1.8.0_171n')
The second element is of the result is the captured output of the stderr stream, which contains the version number.
answered Nov 13 '18 at 1:32
metatoastermetatoaster
9,76212640
answered Nov 13 '18 at 1:32
metatoastermetatoaster
9,76212640
answered Nov 13 '18 at 1:32
metatoastermetatoaster
9,76212640
answered Nov 13 '18 at 1:32
metatoastermetatoaster
9,76212640
9,76212640
Wow okay, this is very interesting. Thank you for awnsering my question. I have a secondary question is there any reason for it returning it to stderr?
– SomeSimpleton
Nov 13 '18 at 1:36
The developers behind it might think that those particular output don't belong to the standard stream - however, these kind of decisions are up to whoever that wrote the program so you will have to ask them.
– metatoaster
Nov 13 '18 at 1:47
add a comment |
Wow okay, this is very interesting. Thank you for awnsering my question. I have a secondary question is there any reason for it returning it to stderr?
– SomeSimpleton
Nov 13 '18 at 1:36
The developers behind it might think that those particular output don't belong to the standard stream - however, these kind of decisions are up to whoever that wrote the program so you will have to ask them.
– metatoaster
Nov 13 '18 at 1:47
Wow okay, this is very interesting. Thank you for awnsering my question. I have a secondary question is there any reason for it returning it to stderr?
– SomeSimpleton
Nov 13 '18 at 1:36
Wow okay, this is very interesting. Thank you for awnsering my question. I have a secondary question is there any reason for it returning it to stderr?
– SomeSimpleton
Nov 13 '18 at 1:36
The developers behind it might think that those particular output don't belong to the standard stream - however, these kind of decisions are up to whoever that wrote the program so you will have to ask them.
– metatoaster
Nov 13 '18 at 1:47
The developers behind it might think that those particular output don't belong to the standard stream - however, these kind of decisions are up to whoever that wrote the program so you will have to ask them.
– metatoaster
Nov 13 '18 at 1:47
add a comment |
This will only work on *nix:
import commands
print commands.getstatusoutput('javac -version')
answered Nov 13 '18 at 1:22
Madison CourtoMadison Courto
424212
Okay this one worked. Thank you
– SomeSimpleton
Nov 13 '18 at 1:34
Would you mind marking as answered please
– Madison Courto
Dec 24 '18 at 17:41
add a comment |
This will only work on *nix:
import commands
print commands.getstatusoutput('javac -version')
answered Nov 13 '18 at 1:22
Madison CourtoMadison Courto
424212
Okay this one worked. Thank you
– SomeSimpleton
Nov 13 '18 at 1:34
Would you mind marking as answered please
– Madison Courto
Dec 24 '18 at 17:41
add a comment |
This will only work on *nix:
import commands
print commands.getstatusoutput('javac -version')
answered Nov 13 '18 at 1:22
Madison CourtoMadison Courto
424212
This will only work on *nix:
import commands
print commands.getstatusoutput('javac -version')
answered Nov 13 '18 at 1:22
Madison CourtoMadison Courto
424212
answered Nov 13 '18 at 1:22
Madison CourtoMadison Courto
424212
answered Nov 13 '18 at 1:22
Madison CourtoMadison Courto
424212
answered Nov 13 '18 at 1:22
Madison CourtoMadison Courto
424212
424212
Okay this one worked. Thank you
– SomeSimpleton
Nov 13 '18 at 1:34
Would you mind marking as answered please
– Madison Courto
Dec 24 '18 at 17:41
add a comment |
Okay this one worked. Thank you
– SomeSimpleton
Nov 13 '18 at 1:34
Would you mind marking as answered please
– Madison Courto
Dec 24 '18 at 17:41
Okay this one worked. Thank you
– SomeSimpleton
Nov 13 '18 at 1:34
Okay this one worked. Thank you
– SomeSimpleton
Nov 13 '18 at 1:34
Would you mind marking as answered please
– Madison Courto
Dec 24 '18 at 17:41
Would you mind marking as answered please
– Madison Courto
Dec 24 '18 at 17:41
add a comment |
Thank you to the few fellas that answered the question. The output is being put out to stderr instead of stdout. Thank you to everyone
answered Nov 13 '18 at 17:37
SomeSimpletonSomeSimpleton
84
add a comment |
Thank you to the few fellas that answered the question. The output is being put out to stderr instead of stdout. Thank you to everyone
answered Nov 13 '18 at 17:37
SomeSimpletonSomeSimpleton
84
add a comment |
Thank you to the few fellas that answered the question. The output is being put out to stderr instead of stdout. Thank you to everyone
answered Nov 13 '18 at 17:37
SomeSimpletonSomeSimpleton
84
Thank you to the few fellas that answered the question. The output is being put out to stderr instead of stdout. Thank you to everyone
answered Nov 13 '18 at 17:37
SomeSimpletonSomeSimpleton
84
answered Nov 13 '18 at 17:37
SomeSimpletonSomeSimpleton
84
answered Nov 13 '18 at 17:37
SomeSimpletonSomeSimpleton
84
answered Nov 13 '18 at 17:37
SomeSimpletonSomeSimpleton
84
84
add a comment |
add a comment |
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Possible solution might be giving complete path for "javac". Also, PIPE stderr as well and check it. You might find something there
– Shriroop Joshi
Nov 13 '18 at 1:30