Currently I am setting time zone GMT+5 on my Linux CentOS 7 machine by linking /etc/localtime to /usr/share/zoneinfo/Etc/GMT-5.
I want to create a zone info file for example
/usr/share/zoneinfo/Etc/GMT-5:30 that enables me to set the current timezone to GMT+5:30 without having to worry about DST changes.
I am aware that I could link
/usr/share/zoneinfo/Asia/Kolkata for example but then I will have to worry about DST changes even if it may not be implemented in the mean time.
Also I am aware of
TZ=GMT+5:30; export $TZ but I am worried that this approach backfire for some reason in the future.