Running a Script- and debugging.

[Jim]

On 09/23/2009 12:11 AM, Nifty Fedora Mitch wrote:
> On Tue, Sep 22, 2009 at 05:17:34PM -0430, Patrick O'Callaghan wrote:
>    
>> On Tue, 2009-09-22 at 15:46 -0400, Jim wrote:
>>      
>>> Could someone give me a Ideal as to this part of a script would
>>> hangup
>>> script.
>>> In FC11.
>>>
>>> The hangup stops at;
>>>
>>> cd 'dirname $0'
>>>        
>> $0 is usually the name of the script itself, so 'dirname $0' is the
>> directory the script lives in. Changing to that directory shouldn't
>> normally cause a hang, unless for example the directory is NFS-mounted,
>> but without more information this is pure speculation.
>>
>>      
> Put some debugging in the script it is easy to make a copy.
> We do not know what $0 is.
>
> We could have changed directory as expected and the
> next command is hanging ya out to dry.  What is
> the next command.  Is there a "trap" that has taken
> the script to someplace unexpected.
>
> Also 'odd' things can happen if '.' and strange places
> are in your PATH.   Are you running it as root via "su",
> as root via "su -", as root via "sudo" or as yourself.
>
> What is the first line.  Is this a sh, bash or csh script or something else.
> Some flags may be passed,
>
> To the copy add simple commands to get you some additional
> information.
>
> Ideas....
> $ cat bin/flubber
> #!/bin/bash
> pwd
> echo foo
> echo $0
> dirname $0
> cd 'dirname $0'
> pwd
>
> =====
> $ bin/flubber
> /home/mydir
> foo
> bin/flubber
> bin
> bin/flubber: line 6: cd: dirname $0: No such file or directory
> /home/mydir
>
> =====
> If it "hangs" you might run it with "strace -f -o /tmp/tracelogfile script"
>
> =====
> I do recall a bug fix going into bash that fixes a standards correctness
> problem but has side effects because is it not "bug" compatable.
> You can grab an OLDer version of bash and install it in a SAFE place
> with rpm and try it.  I just do not recall the details and they do
> not matter -- it is easy to test for.  It is also easy to look at the
> change log for the bash rpm and read the bug reports.  Use rpm or yum,
> Example using rpm:
>   # which bash
>   # rpm -qf /bin/bash
>   # rpm -qi bash
>   # rpm -q --changelog bash
>
>
>
>    
Mitch you DID IT !!  su - instead of su