How to run parent shell script in -x ~debug mode and all child scripts that it calls

[Sangal-Arun]

Hi All,

I have created a shell simple script, but when I'm running it in debug mode say, $ sh -x <mainscript>.sh ....the debugging is done only for this script and not cascading further if this script calls another scripts within its body.

I don't want to put "sh -x" in front of each sub-script that is being called from this main script. Also, I don't want to mention #!/bin/bash -x inside the child/sub scripts that are being called by the main script within its body.

Is this POSSIBLE, if I give sh -x <mainscript>.sh ...and system will automatically cascade the debug behaviour to all sub/child scripts that are called within this mainscript....kindly confirm back...if this is even possible or not.

I'm also trying to figure out whan command can I use to find out ...what all commands (lines) inside a script are called during a script execution and lines inside the sub/child scripts that is called from the mainscript...even if it calls other scripts is same shell or child shell.

Any helps...pls feel free if you want me to clarify my Q? again.
thanks-
/Arun


Script example is given below: where sh-x.sh is the mainscript, it calls sh-x1.sh and sh-x2.sh sub scripts. See the "cat" command output for these 3 files and output which I'm getting while executing "sh-x.sh" with -x option on.

================= thanks==================

[user@build]$ cat sh-x1.sh
#!/bin/bash

echo "script sh-x1.sh has been called ---!"
[user@build]$
[user@build]$ cat sh-x2.sh
#!/bin/bash

echo "script sh-x2.sh has been called ..after ./sh-x1.sh at the same shell level"
[user@build]$
[user@build]$ cat sh-x.sh
#!/bin/bash

echo "arun K sangal"
echo "-------------"
./sh-x1.sh
. ./sh-x2.sh
echo -e "\nDone"

[user@build]$ chmod 700 sh-x.sh sh-x1.sh sh-x2.sh
[user@build]$ ll -tr sh-x*
-rwx------    1 stpuser  webgroup       97 Aug  3 16:53 sh-x.sh
-rwx------    1 stpuser  webgroup       57 Aug  3 17:14 sh-x1.sh
-rwx------    1 stpuser  webgroup       95 Aug  3 17:15 sh-x2.sh
[user@build]$
[user@build]$ ./sh-x.sh
arun K sangal
-------------
script sh-x1.sh has been called ---!
script sh-x2.sh has been called ..after ./sh-x1.sh at the same shell level

Done
[user@build]$ sh -x ./sh-x.sh
+ echo 'arun K sangal'
arun K sangal
+ echo -------------
-------------
+ ./sh-x1.sh
script sh-x1.sh has been called ---!
+ . ./sh-x2.sh
++ echo 'script sh-x2.sh has been called ..after ./sh-x1.sh at the same shell level'
script sh-x2.sh has been called ..after ./sh-x1.sh at the same shell level
+ echo -e '\nDone'

Done
[user@build]$

[Sangal-Arun]

Looks like when I'm running the mainscript "sh-x.sh" with -x and -v option ...I'm getting the desired output for "sh-x2.sh" as it is being called in the same parent shell level.

/Arun

[drl]

Hi.

It looks like you can do this if you cause the variable SHELLOPTS to be in the environment (export), and use set -x (xtrace on). For example:

#!/bin/sh

# @(#) s1       Demonstrate feature.

set -o nounset
echo
echo "GNU bash $BASH_VERSION" >&2
echo

cat >sub1 <<EOF
#!/bin/bash
echo " Hello from sub1."
echo " shellopts sub1 $SHELLOPTS"
exit 0
EOF

cat >sub2 <<EOF
#!/bin/bash
echo " Hello from sub2."
echo " shellopts sub2 $SHELLOPTS"
exit 0
EOF

chmod +x sub1 sub2

echo
echo " SHELLOPTS in main $SHELLOPTS"

echo
echo " Running sub1."
./sub1

echo
echo " Setting xtrace on."
set -x

echo
echo " SHELLOPTS in main $SHELLOPTS"

echo
echo " Running sub2."
./sub2

export SHELLOPTS
echo
echo " Running sub1 again with SHELLOPTS in environment."
./sub1

exit 0

which produces the cascade when the first script is re-run:

% ./s1

GNU bash 2.05b.0(1)-release


 SHELLOPTS in main braceexpand:hashall:interactive-comments:nounset:posix

 Running sub1.
 Hello from sub1.
 shellopts sub1 braceexpand:hashall:interactive-comments:nounset:posix

 Setting xtrace on.
+ echo

+ echo ' SHELLOPTS in main braceexpand:hashall:interactive-comments:nounset:posix:xtrace'
 SHELLOPTS in main braceexpand:hashall:interactive-comments:nounset:posix:xtrace
+ echo

+ echo ' Running sub2.'
 Running sub2.
+ ./sub2
 Hello from sub2.
 shellopts sub2 braceexpand:hashall:interactive-comments:nounset:posix
+ export SHELLOPTS
+ echo

+ echo ' Running sub1 again with SHELLOPTS in environment.'
 Running sub1 again with SHELLOPTS in environment.
+ ./sub1
+ echo ' Hello from sub1.'
 Hello from sub1.
+ echo ' shellopts sub1 braceexpand:hashall:interactive-comments:nounset:posix'
 shellopts sub1 braceexpand:hashall:interactive-comments:nounset:posix
+ exit 0
+ exit 0

However, at a quick glance, it does not seem that the SHELLOPTS value is propagated to the child itself, which means that you'd need to do the same thing in the child to get its children to trace. You could set up an auxiliary script to set debug on / off, and run that in every script of interest.

Perhaps someone will stop by with a more clever answer to this.

See man bash for details ... cheers, drl