A few things about system and IO.popen - what's the current status?

thbar · March 4, 2009, 1:08pm

Hi,

sorry if it’s a know fact - I could not find the info easily. I hope
this
will be useful.

On Windows, system() seems to work partially, is it normal ? The
following
works:

system(“echo hello”)
hello
=> true

the following doesn’t seem to (although svn is in the path):

system(“svn”)
=> false

system(“svn.exe”)
=> false

Still on Windows, it seems that IO.popen crashes (I had a quick look at
IoOps.cs to see if it was implemented):

IO.popen(“svn.exe”) do |io| puts io.read end
:0:in popen': La rÃ©fÃ©rence d'objet n'est pas dÃ©finie Ã une instance d'un objet. (System::NullReferenceException) from :0:inpopen’
from :0

I ran the same stuff on Mono and got:

IronRuby 1.0.0.0 on Mono 2.4
Copyright © Microsoft Corporation. All rights reserved.

system(“blah”)
IronRuby.Libraries:0:in ExecuteProcessAndWait': No such file or directory (Errno::ENOENT) from IronRuby.Libraries:0:inExecuteCommandInShell’
from :0:in `system’

system(“svn”)
=> nil

system(“svn > svninfo.txt”)
=> nil

exit

Finally, running IO.popen on Mono gives the same output as Windows:
IronRuby 1.0.0.0 on Mono 2.4
Copyright © Microsoft Corporation. All rights reserved.

IO.popen(“svn.exe”) { |io| puts io.read }
:0:in popen': Object reference not set to an instance of an object (System::NullReferenceException) from :0:inpopen’

So my question is: what’s the current status on system and IO.popen ? Is
it
supposed to work and is it a regression, or is it not fully implemented
?

I may be able to help at some point here (either by providing patches or
testing on Mono + Windows) if it’s not your top priority

Given that I use Ruby to glue things together quite a lot, that would be
useful to me.

cheers,

– Thibaut

thbar · March 4, 2009, 5:42pm

Implementations of both “system” and “popen” are not solid. Any help
here is very much appreciated! Feel free to submit patches and also new
specs for these methods. Let us know if you need some changes in runtime
(IronRuby.dll) since this assembly is not open to contributions just yet
(but we might be able to factor some stuff out to libraries or provide
the necessary functionality needed in core).

BTW, our tag file for Kernel#system contains this suppressions:

fails:Kernel#system can run basic things that exist
fails:Kernel#system returns false when it can’t
fails:Kernel#system does not write to stderr when it can’t find a
command
fails:Kernel#system uses /bin/sh if freaky shit is in the command
fails:Kernel#system is a private method
fails:Kernel#system expands shell variables when given a single string
argument
fails:Kernel#system does not expand shell variables when given multiples
arguments

Tomas

From: [email protected]
[mailto:[email protected]] On Behalf Of Thibaut
BarrÃ¨re
Sent: Wednesday, March 04, 2009 3:37 AM
To: ironruby-core
Subject: [Ironruby-core] A few things about system and IO.popen - what’s
the current status ?

Hi,

sorry if it’s a know fact - I could not find the info easily. I hope
this will be useful.

On Windows, system() seems to work partially, is it normal ? The
following works:

system(“echo hello”)
hello
=> true

the following doesn’t seem to (although svn is in the path):

system(“svn”)
=> false
system(“svn.exe”)
=> false

Still on Windows, it seems that IO.popen crashes (I had a quick look at
IoOps.cs to see if it was implemented):

IO.popen(“svn.exe”) do |io| puts io.read end
:0:in popen': La rÃ©fÃ©rence d'objet n'est pas dÃ©finie Ã une instance d'un objet. (System::NullReferenceException) from :0:in popen’
from :0

I ran the same stuff on Mono and got:

IronRuby 1.0.0.0 on Mono 2.4
Copyright (c) Microsoft Corporation. All rights reserved.

system(“blah”)
IronRuby.Libraries:0:in ExecuteProcessAndWait': No such file or directory (Errno::ENOENT) from IronRuby.Libraries:0:in ExecuteCommandInShell’
from :0:in `system’

system(“svn”)
=> nil
system(“svn > svninfo.txt”)
=> nil
exit

Finally, running IO.popen on Mono gives the same output as Windows:

IronRuby 1.0.0.0 on Mono 2.4
Copyright (c) Microsoft Corporation. All rights reserved.

IO.popen(“svn.exe”) { |io| puts io.read }
:0:in popen': Object reference not set to an instance of an object (System::NullReferenceException) from :0:in popen’

So my question is: what’s the current status on system and IO.popen ? Is
it supposed to work and is it a regression, or is it not fully
implemented ?

I may be able to help at some point here (either by providing patches or
testing on Mono + Windows) if it’s not your top priority

Given that I use Ruby to glue things together quite a lot, that would be
useful to me.

cheers,

– Thibaut

thbar · March 4, 2009, 6:24pm

I don’t know how the semantics differ from Ruby’s, but someone
interested in doing this could probably adapt the IronPython source
code. These functions should be in “nt.cs”.

From: [email protected]
[mailto:[email protected]] On Behalf Of Tomas M.
Sent: Wednesday, March 04, 2009 8:42 AM
To: [email protected]
Subject: Re: [Ironruby-core] A few things about system and IO.popen -
what’s the current status ?

Implementations of both “system” and “popen” are not solid. Any help
here is very much appreciated! Feel free to submit patches and also new
specs for these methods. Let us know if you need some changes in runtime
(IronRuby.dll) since this assembly is not open to contributions just yet
(but we might be able to factor some stuff out to libraries or provide
the necessary functionality needed in core).

BTW, our tag file for Kernel#system contains this suppressions:

fails:Kernel#system can run basic things that exist
fails:Kernel#system returns false when it can’t
fails:Kernel#system does not write to stderr when it can’t find a
command
fails:Kernel#system uses /bin/sh if freaky shit is in the command
fails:Kernel#system is a private method
fails:Kernel#system expands shell variables when given a single string
argument
fails:Kernel#system does not expand shell variables when given multiples
arguments

Tomas

From: [email protected]
[mailto:[email protected]] On Behalf Of Thibaut
BarrÃ¨re
Sent: Wednesday, March 04, 2009 3:37 AM
To: ironruby-core
Subject: [Ironruby-core] A few things about system and IO.popen - what’s
the current status ?

Hi,

sorry if it’s a know fact - I could not find the info easily. I hope
this will be useful.

On Windows, system() seems to work partially, is it normal ? The
following works:

system(“echo hello”)
hello
=> true

the following doesn’t seem to (although svn is in the path):

system(“svn”)
=> false
system(“svn.exe”)
=> false

Still on Windows, it seems that IO.popen crashes (I had a quick look at
IoOps.cs to see if it was implemented):

IO.popen(“svn.exe”) do |io| puts io.read end
:0:in popen': La rÃ©fÃ©rence d'objet n'est pas dÃ©finie Ã une instance d'un objet. (System::NullReferenceException) from :0:in popen’
from :0

I ran the same stuff on Mono and got:

system(“blah”)
IronRuby.Libraries:0:in ExecuteProcessAndWait': No such file or directory (Errno::ENOENT) from IronRuby.Libraries:0:in ExecuteCommandInShell’
from :0:in `system’

system(“svn”)
=> nil
system(“svn > svninfo.txt”)
=> nil
exit

Finally, running IO.popen on Mono gives the same output as Windows:

IO.popen(“svn.exe”) { |io| puts io.read }
:0:in popen': Object reference not set to an instance of an object (System::NullReferenceException) from :0:in popen’

So my question is: what’s the current status on system and IO.popen ? Is
it supposed to work and is it a regression, or is it not fully
implemented ?

I may be able to help at some point here (either by providing patches or
testing on Mono + Windows) if it’s not your top priority

Given that I use Ruby to glue things together quite a lot, that would be
useful to me.

cheers,

– Thibaut

thbar · March 4, 2009, 10:17pm

Hi,

thanks for the pointers. I’ll first have to learn how to compile and
launch the specs on my machine.

If I manage to get something useful, I’ll report back.

cheers,

– Thibaut