Cron with Tcl

[Garima]

Hi,

I am having problems with running a tcl script with Cron. I have read
the past few threads on this topic on this group but still not able
to solve the problem.

first few lines of the script
==================
#!/bin/sh
# the next line restarts using tclsh \
exec tclsh "$0" "$@"

I have run this script from the command line and tried it in the
following ways:

/home/garima/automation/scripts/Apcon/save_preset.tcl
tclsh /home/garima/automation/scripts/Apcon/save_preset.tcl

This is how my cron looks like:

*/5 * * * * /usr/bin/mrtg /usr/local/apache2/mrtg/
mrtg.cfg <-- this runs
*/2 * * * * /home/garima/automation/scripts/Apcon/save_preset.tcl

I am a cron newbie and will appreciate any help on this topic.

Thanks,
Garima

[Uwe Klein]

What is in your crontab?

in mine I find:
# the shell to run as "sh"
SHELL=/bin/sh
# is your path right to find "tclsh" ?
PATH=/usr/bin:/usr/sbin:/sbin:/bin
# mail uncaptured output to some user of your choosing:
# use this, what ever goes wrong the mailed output should show you!
MAILTO=myself

uwe

[Garima]

Sorry, it was the following all along and may be I changed it
momentarily.

#/usr/bin

# the next line restarts using tclsh \
exec tclsh "$0" "$@"

Even with the above 3 lines it doesn't work :(

[root@vm-linux-1 Apcon]# whereis tclsh
tclsh: /usr/bin/tclsh8.4 /usr/bin/tclsh /usr/share/man/man1/tclsh.1.gz
[root@vm-linux-1 Apcon]#

[root@vm-linux-1 Apcon]# printenv | grep PATH
PATH=/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/bin:/bin:/usr/
bin:/usr/X11R6/bin:/home/garima/bin:/usr/local/sbin:/sbin:/bin:/usr/
sbin:/usr/bin
[root@vm-linux-1 Apcon]#

Thanks for your quick response.
-Garima

On May 11, 12:55 pm, Uwe Klein <uwe_klein_habertw...@t-online.de>
wrote:

[Christian Nassau]

Garima schrieb:

> Sorry, it was the following all along and may be I changed it
> momentarily.
>
> #/usr/bin
> # the next line restarts using tclsh \
> exec tclsh "$0" "$@"
>
> Even with the above 3 lines it doesn't work :(

Does the following do the trick?

#/usr/bin/tclsh
# no need to restart - alread running tclsh

--
=> Christian Nassau, http://www.nullhomotopie.de

[Garima]

I just have the following in my script :

#!/usr/bin/tclsh

source /home/garima/automation/library/src

<removed the 2 unwanted lines>

With whatever I do, I can run it from the command line but the cron
is not running it.

Appreciate all your help!
-Garima

[Uwe Klein]

Garima wrote:
> Sorry, it was the following all along and may be I changed it
> momentarily.

your original script was OK
>

## save_preset.tcl ########################################

#!/bin/sh
# the next line restarts using tclsh \
exec tclsh "$0" "$@"

# your stuff

# end of script
#####################################################

now look into your crontab via "crontab -e"

# crontab ##############################################
SHELL=/bin/sh
# is your path right to find "tclsh" ( you found it in /usr/bin ?

PATH=/usr/bin:/usr/sbin:/sbin:/bin
# mail uncaptured output to some user of your choosing:
# use this, what ever goes wrong the mailed output should show you!

MAILTO=garima

*/5 * * * * /usr/bin/mrtg /usr/local/apache2/mrtg/mrtg.cfg
<-- this runs

*/2 * * * * /home/garima/automation/scripts/Apcon/save_preset.tcl

# end of crontab
#############################################################

if the PATH shell variable is set as shown above
the second line will run too.

>
>
G!
uwe

[Garima]

Great !! After adding the lines you told me to in my crontab I got
pass the first hurdle. Thank you very much!

I am seeking some further assistance from you. In the email I get the
following output: Looks like it is complaining about the
stty -echo. As this is a proc written by someone else, I am not sure
how it will alter the working of the proc if I removed "stty -echo".
But I temporarily removed
it and the script runs completely. Would you know a workaround? I know
I am getting to an expect problem now.

======================OUTPUT====================
date is 14

spawn telnet 10.1.1.10
Trying 10.1.1.10...

Connected to 10.1.1.10.

Escape character is '^]'.

2007-03-22 19:57:15
Thanks for choosing Apcon

login: lab
password:

Apcon CmdX 2.86, Copyright (C) 2004-2006
10.1.1.10>> :
<parsePrompt> INFO: The prompt is 10.1.1.10
<connect> INFO: SpawnId is exp3
<connect> INFO: prompt is 10.1.1.10

preset num is 14
stty: impossible in this context
are you disconnected or in a batch, at, or cron script?stty:
ioctl(user): bad file number

while executing
"stty -echo"
(procedure "sendCommand" line 6)
invoked from within
"sendCommand $ip_add1 $cmdString"
(file "/home/garima/automation/scripts/Apcon/save_preset.tcl" line
25)

===============================================================================

On May 11, 1:53 pm, Uwe Klein <uwe_klein_habertw...@t-online.de>
wrote:

[Uwe Klein]

stty is a unix command _and_ an
equivalent command in provided by expect
with about the same functionality.

your script looks line an expect script

because of commands like
stty
spawn
expect
(exp_)send

you will have to either run it with expect
instead of tclsh like this:

#!/bin/sh
# the next line restarts using tclsh \

exec expect "$0" "$@"

or add a
package require expect

in your tcl script like this:

#!/bin/sh
# the next line restarts using tclsh \
exec tclsh "$0" "$@"

package require expect

source /...

uwe

[Garima]

Looks like the following doesn't do the trick.
I still get the same error.

====================

#!/bin/sh
# the next line restarts using tclsh \
exec tclsh "$0" "$@"

package require Expect

=====================

Error
====

stty: impossible in this context
are you disconnected or in a batch, at, or cron script?stty:
ioctl(user): bad file number

while executing
"stty -echo"
(procedure "sendCommand" line 6)
invoked from within
"sendCommand $ip_add1 $cmdString"
(file "/home/garima/automation/scripts/Apcon/save_preset.tcl" line

26)

Thanks very much again!

-----------------------------------------

[Bruce Hartweg]

in addition to making sure you run with expect, the stty issue is that
when running under cron there is no tty, so trying to operate on it is
a bad idea.

you need to remove the offending code, or do some checking into what
environment you are running under before calling it.

Bruce

[Uwe Klein]

Garima wrote:
> Looks like the following doesn't do the trick.
> I still get the same error.
>
> ====================
> #!/bin/sh
> # the next line restarts using tclsh \
> exec tclsh "$0" "$@"
>
> package require Expect
>
> =====================
>
> Error
> ====
> stty: impossible in this context
> are you disconnected or in a batch, at, or cron script?stty:
> ioctl(user): bad file number
>
> while executing
> "stty -echo"
> (procedure "sendCommand" line 6)
> invoked from within
> "sendCommand $ip_add1 $cmdString"
> (file "/home/garima/automation/scripts/Apcon/save_preset.tcl" line
> 26)
>
> Thanks very much again!

could you post the complete script you are running?

Does your app request a password or other input from
the user when run in interactive mode.

uwe

[Uwe Klein]

bruce wrote

> in addition to making sure you run with expect, the stty issue is that
> when running under cron there is no tty, so trying to operate on it is
> a bad idea.
>
> you need to remove the offending code, or do some checking into what
> environment you are running under before calling it.

One could wrap the whole stuff in another layer of expect ;-)

uwe

[Garima]

On May 11, 3:38 pm, Uwe Klein <uwe_klein_habertw...@t-online.de>
wrote:

No there is no interaction with the user. The passwords are hard coded
in the
script. Of course, I am calling procs from other lib files.

Oh well, if using stty is not possible, I might just get rid of it
after one meeting.
I don't even understand what those sttys are doing for us. :-)

#!/bin/sh
# the next line restarts using tclsh \
exec tclsh "$0" "$@"

package require Expect

source /home/garima/automation/library/src

set ip_add1 "10.1.1.10"
set ip_add2 "10.1.1.11"
set platformType "Apcon"
set mydate [exec date +%e]

connect $ip_add1 $platformType -login test -password test -service
telnet
connect $ip_add2 $platformType -login test -password test -service
telnet

set presetNum 14
set location "/home/lab/configs/"
set tmpDate [eval "exec date" ]

puts "preset num is $presetNum"
set cmdString "show preset settings $presetNum"
sendCommand $ip_add1 $cmdString
sendCommand $ip_add2 $cmdString

if {$presetNum == 0 } {
set presetNum 10
}

sendCommand $ip_add1 $cmdString
sendCommand $ip_add2 $cmdString

set myhour [exec date +%H]
set cmdString "set preset current $presetNum"
sendCommand $ip_add1 $cmdString
sendCommand $ip_add2 $cmdString
set destFile [attachTimeStamp $tmpDate $ip_add1]
set op [sendCommand $ip_add1 "show preset settings $presetNum" ]
regexp {:\s*([0-9A-Z]*)} $op match var1
writeBufferFile $var1 $location/Apcon/$destFile

# Redoing these 4 steps for Apcon Chassis 2

set destFile [attachTimeStamp $tmpDate $ip_add2]
set op [sendCommand $ip_add2 "show preset settings $presetNum" ]
regexp {:\s*([0-9A-Z]*)} $op match var1
writeBufferFile $var1 $location/Apcon/$destFile

closeSession $ip_add1
closeSession $ip_add2

[Bezoar]

On May 11, 2:50 pm, Uwe Klein <uwe_klein_habertw...@t-online.de>
wrote:

You can experiment by calling spawn with the -nottyinit option to
avoid calling stty altogether. I have also
seen in other groups that not expecting eof can also cause the expect
to "not run". so
at then of expect script have "expect eof". People have been running
expect from crontab for years so
this is not the problem. It is more likely that what you are spawning
cannot run without a terminal.
Again a script showing what you are trying to do would help.

Carl

[Uwe Klein]

Bezoar wrote:

> this is not the problem. It is more likely that what you are spawning
> cannot run without a terminal.

if you do a spawn in expect the process is connected via a pty pair
which look suspiciously like a tty on the "other" side.

uwe

[Neil Madden]

Garima wrote:
...

>
> No there is no interaction with the user. The passwords are hard coded
> in the
> script. Of course, I am calling procs from other lib files.
>
> Oh well, if using stty is not possible, I might just get rid of it
> after one meeting.
> I don't even understand what those sttys are doing for us. :-)

stty -echo turns off character echoing for the terminal, and is used
when inputting passwords typically. Obviously if you are providing the
password in the script then you don't need these stty calls.

> #!/bin/sh
> # the next line restarts using tclsh \
> exec tclsh "$0" "$@"
>
> package require Expect
>
> source /home/garima/automation/library/src
>
> set ip_add1 "10.1.1.10"
> set ip_add2 "10.1.1.11"
> set platformType "Apcon"
> set mydate [exec date +%e]

As a tip, Tcl has a built-in [clock] command which you could replace all
the calls to [exec date], e.g.:

set mydate [clock format [clock seconds] -format %e]

-- Neil

[Larry W. Virden]

On May 11, 12:43 pm, Garima <garimase...@gmail.com> wrote:
> I am having problems with running a tcl script with Cron.

I'd suggest solving this problem in steps. First, get this working

$ cat step1.tcl
#! /bin/sh

# the next line restarts using tclsh \
exec tclsh "$0" "$@"

puts "script is running"
$

Once the above is running, then you know that any other problems you
are having are later in your tclsh script itself.

[Larry W. Virden]

On May 11, 3:29 pm, Garima <garimase...@gmail.com> wrote:
> Looks like the following doesn't do the trick.
> I still get the same error.

> =====================

>
> Error
> ====
> stty: impossible in this context
> are you disconnected or in a batch, at, or cron script?stty:
> ioctl(user): bad file number

Read about the Tcl command called "catch". Check, for instance,
http://wiki.tcl.tk/catch . Adding catch around some commands like this
will at least let you get farther.

The stty is a command that interacts with one's keyboard. Of course,
in a cron, there is no keyboard. There are ways to code things so that
these types of errors don't arise, but it sounds to me as if you are a
_user_ of Tcl rather than a developer, so this might be a bit more
than you are ready to handle.

If that's the case, you might need to find out if there is a developer
community for this application, and ask there if anyone could help add
some bullet-proofing for cases like this.

[Glenn Jackman]

At 2007-05-11 04:02PM, "Garima" wrote:
> On May 11, 3:38 pm, Uwe Klein <uwe_klein_habertw...@t-online.de>
> wrote:
> > Garima wrote:
> > > stty: impossible in this context
> > > are you disconnected or in a batch, at, or cron script?stty:
> > > ioctl(user): bad file number
> >
> > > while executing
> > > "stty -echo"
> > > (procedure "sendCommand" line 6)
> > > invoked from within
> > > "sendCommand $ip_add1 $cmdString"
> > > (file "/home/garima/automation/scripts/Apcon/save_preset.tcl" line
> > > 26)

[...]

> #!/bin/sh
> # the next line restarts using tclsh \
> exec tclsh "$0" "$@"
>
> package require Expect
>
> source /home/garima/automation/library/src

[... lines that don't reference 'stty' ...]
> sendCommand $ip_add1 $cmdString

You could show us that src file so we can see what sendCommand is and
how stty is being used.

To me, you need to edit the file containing sendCommand to wrap any stty
calls with expect:

catch {stty -echo}
#...
catch {stty echo}

--
Glenn Jackman
"You can only be young once. But you can always be immature." -- Dave Barry