RE: Environment variable "PS4" can not be passed to bash script from version 4.2.46(2)

[Chen, Farrah]

Got it, thanks for the info.


Thanks,
Fan



-----Original Message-----
From: Chet Ramey [mailto:chet.ramey@case.edu] 
Sent: Wednesday, October 24, 2018 4:48 AM
To: Chen, Farrah <farrah.chen@intel.com>; bug-bash@gnu.org
Cc: chet.ramey@case.edu
Subject: Re: Environment variable "PS4" can not be passed to bash script from 
version 4.2.46(2)

On 10/23/18 12:06 PM, Greg Wooledge wrote:
> On Tue, Oct 23, 2018 at 03:20:12PM +0000, Chen, Farrah wrote:
>> But in Bash script, it cannot work, it keeps its original value:
>> [root@fchen ~]# cat test.sh
>> #!/usr/bin/bash
>> echo $PS4
>> echo $FAN
> 
> This is because you're doing it as root.  Bash strips PS4 from the 
> environment when started as root, as a security precaution.

That change came in in bash-4.3 (patch 48). His vendor probably patched their 
version of bash-4.2 to do the same thing.

--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/