Should SHOPT_SYSRC and the code predicated on it be removed?

[krader1961]

The SHOPT_SYSRC symbol is another build time option I stumbled across. It is not enabled by default in the 2016-01-10-beta branch. It is not enabled in the current master branch. From lib/package/ast-open.README:

05-03-25 +Building ksh with SHOPT_SYSRC=1 causes interactive ksh to source
          /etc/ksh.kshrc (if it exists) before sourcing the $ENV file.

This feature should either be enabled unconditionally or removed. We should not be enabling people to build ksh with features enabled or disabled based solely on their whims without regard to whether the platform requires a specific choice (in which case we should auto-detect it at build time).

[dannyweldon]

I just checked the system ksh on my ubuntu 16.04 machine:

$ strings /usr/bin/ksh | grep kshrc
%s/.kshrc
/etc/ksh.kshrc
/etc/ksh.kshrc
${ENV-$HOME/.kshrc}
.kshrc

Then I checked my very out-of-date rhel7 vm and it does not have the /etc/ksh.kshrc references.

[catull]

Searching for strings in the binary I downloaded years ago for macOS 10.6(?) reveals ...

strings ksh.2012-08-06.darwin.i386-64 | fgrep kshrc

%s/.kshrc
.kshrc
${ENV-$HOME/.kshrc}

Even if this shows a different configuration, I favour the unconditional inclusion of the code.
If the file /etc/ksh.kshrc` does exist, it should be sourced.

macOS does not come with /etc/ksh.kshrc.
Thus including the code has no impact on this platform.

+1 on unconditional inclusion of code, i.e. removal of #if SHOPT_SYSRC/#endif only!

Having said that ....

strings ksh.2012-08-06.darwin.i386-64| fgrep /etc

shows

/etc/ksh_audit
/etc/profile
/etc/suid_profile
/etc/suid_exec
/etc/profile

@dannyweldon
Can you confirm these, too ?

[krader1961]

The /etc/ksh_audit file is issue #240. The other paths appear to be enabled unconditionally in the current code base.

[dannyweldon]

From ubuntu 16.04:

$ strings /usr/bin/ksh | grep /etc
/etc/ksh_audit
/etc/suid_exec
/etc/ksh.kshrc
/etc/suid_profile
/etc/profile
/etc/profile
/etc/ksh.kshrc
/etc/mtab

From my rhel7 vm:

$ strings /bin/ksh | grep /etc
/etc/ksh_audit
/etc/suid_exec
/etc/suid_profile
/etc/profile
/etc/profile
/etc/mtab

[krader1961]

I am not convinced the SHOPT_SYSRC feature is worthwhile but since it is enabled in some distros (e.g., Ubuntu) we should enable it unconditionally. So I'm going to remove that symbol and unconditionally compile the code predicated on it. This type of feature should not be at the discretion of a particular OS distro. OS distros that don't want to support it can simply omit providing a /etc/ksh.kshrc file.

We should not be making it trivial for people to build ksh variants that behave in fundamentally different ways unrelated to the quirks of a specific architecture.