Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss
communicate with external process via pty
45 views
Skip to first unread message
Tim Arnold
Oct 9, 2012, 3:44:49 PM10/9/12
to
I have an external process, 'tralics' that emits mathml when you feed it
latex equations. I want to get that mathml into a string.
The problem for me is that tralics wants to talk to a tty and I've never
done that before; it basically starts its own subshell.
I have the following code which works for simple things. I'm not sure
this is the best way though: basically I got this from google...
import os,sys
import subprocess
import shlex
import pty
cmd = 'tralics --interactivemath'
(master, slave) = pty.openpty()
p = subprocess.Popen(shlex.split(cmd),close_fds=True,
stdin=slave,stdout=slave,stderr=slave)
os.read(master,1024) # start the process
os.write(master,'$\sqrt{x}$\n') # feed it an equation
mathml.append(os.read(master,1024)) # get the mathml in a string
os.write(master,'$\sqrt{x}$\n') # feed more equations
mathml.append(os.read(master,1024)) # get the next string
Any suggestions for improvement?
thanks,
--Tim
latex equations. I want to get that mathml into a string.
The problem for me is that tralics wants to talk to a tty and I've never
done that before; it basically starts its own subshell.
I have the following code which works for simple things. I'm not sure
this is the best way though: basically I got this from google...
import os,sys
import subprocess
import shlex
import pty
cmd = 'tralics --interactivemath'
(master, slave) = pty.openpty()
p = subprocess.Popen(shlex.split(cmd),close_fds=True,
stdin=slave,stdout=slave,stderr=slave)
os.read(master,1024) # start the process
os.write(master,'$\sqrt{x}$\n') # feed it an equation
mathml.append(os.read(master,1024)) # get the mathml in a string
os.write(master,'$\sqrt{x}$\n') # feed more equations
mathml.append(os.read(master,1024)) # get the next string
Any suggestions for improvement?
thanks,
--Tim
Peter Otten
Oct 10, 2012, 2:59:04 AM10/10/12
to pytho...@python.org
Tim
Oct 10, 2012, 3:23:31 PM10/10/12
to pytho...@python.org
On Wednesday, October 10, 2012 2:58:55 AM UTC-4, Peter Otten wrote:
import pexpect
c = pexpect.spawn('tralics --interactivemath')
c.expect('>')
c.sendline('$x+y=z$')
c.expect("<formula.*formula>")
print c.math.group()
c.expect('>')
c.sendline('$a+b=c$')
c.expect("<formula.*formula>")
print c.math.group()
etc.
thanks,
--Tim
> Tim Arnold wrote:
>
> > import os,sys
> > import subprocess
> > import shlex
> > import pty
> > cmd = 'tralics --interactivemath'
> > (master, slave) = pty.openpty()
> > p = subprocess.Popen(shlex.split(cmd),close_fds=True,
> > stdin=slave,stdout=slave,stderr=slave)
> >
> > os.read(master,1024) # start the process
> > os.write(master,'$\sqrt{x}$\n') # feed it an equation
> > mathml.append(os.read(master,1024)) # get the mathml in a string
> > os.write(master,'$\sqrt{x}$\n') # feed more equations
> > mathml.append(os.read(master,1024)) # get the next string
>
>
Thanks Peter. I knew of it, but hadn't tried it. I've been playing with it today and I think it should work fine for my project. With some help from stackoverflow, this seems to do what I need:
>
> > import os,sys
> > import subprocess
> > import shlex
> > import pty
> > cmd = 'tralics --interactivemath'
> > (master, slave) = pty.openpty()
> > p = subprocess.Popen(shlex.split(cmd),close_fds=True,
> > stdin=slave,stdout=slave,stderr=slave)
> >
> > os.read(master,1024) # start the process
> > os.write(master,'$\sqrt{x}$\n') # feed it an equation
> > mathml.append(os.read(master,1024)) # get the mathml in a string
> > os.write(master,'$\sqrt{x}$\n') # feed more equations
> > mathml.append(os.read(master,1024)) # get the next string
>
>
import pexpect
c = pexpect.spawn('tralics --interactivemath')
c.expect('>')
c.sendline('$x+y=z$')
c.expect("<formula.*formula>")
print c.math.group()
c.expect('>')
c.sendline('$a+b=c$')
c.expect("<formula.*formula>")
print c.math.group()
etc.
thanks,
--Tim
Tim
Oct 10, 2012, 3:23:31 PM10/10/12
to comp.lan...@googlegroups.com, pytho...@python.org
On Wednesday, October 10, 2012 2:58:55 AM UTC-4, Peter Otten wrote:
> Tim Arnold wrote:
>
> Tim Arnold wrote:
>
> > import os,sys
> > import subprocess
> > import shlex
> > import pty
> > cmd = 'tralics --interactivemath'
> > (master, slave) = pty.openpty()
> > p = subprocess.Popen(shlex.split(cmd),close_fds=True,
> > stdin=slave,stdout=slave,stderr=slave)
> >
> > os.read(master,1024) # start the process
> > os.write(master,'$\sqrt{x}$\n') # feed it an equation
> > mathml.append(os.read(master,1024)) # get the mathml in a string
> > os.write(master,'$\sqrt{x}$\n') # feed more equations
> > mathml.append(os.read(master,1024)) # get the next string
>
>
> > import subprocess
> > import shlex
> > import pty
> > cmd = 'tralics --interactivemath'
> > (master, slave) = pty.openpty()
> > p = subprocess.Popen(shlex.split(cmd),close_fds=True,
> > stdin=slave,stdout=slave,stderr=slave)
> >
> > os.read(master,1024) # start the process
> > os.write(master,'$\sqrt{x}$\n') # feed it an equation
> > mathml.append(os.read(master,1024)) # get the mathml in a string
> > os.write(master,'$\sqrt{x}$\n') # feed more equations
> > mathml.append(os.read(master,1024)) # get the next string
>
>
0 new messages