(Q) What is this thing?
(A) Like the title says, it displays the environmental variables
Gophernicus generates and references for CGI scripts, etc.
A regex filter is provided for narrowing results.
(Q) Are these ALL the variables?
(A) No, depending on the OS platform and build options there may
be others such as _rc_pid, _rc_original_{stdout,stderr}_fd ;
these are mostly not useful and so not displayed here.
(Q) Is filtering case-sensitive?
(A) No, since all the variables displayed here are upper-case,
any lower-case alphabetic filter terms are capitalized.
(Q) What is a "regex" filter?
(A) The term "regex" is a contraction of "regular expressions"
which are commonly used with UNIX shell scripts, tools like
grep(1) and sed(1), and various scripting languages such as
AWK, Perl and Python.
(Q) What are some regex filter examples?
(A) Some basic examples are shown below:
^server => matches vars starting w/ "SERVER"
addr$ => matches vars ending w/ "ADDR"
(http|goph) => matches vars containing "HTTP" or "GOPH"
^[a-z]+$ => matches vars only containing A-Z (no "_")
t{2} => matches vars containing "TT"
[qv]+ => matches vars with one or more "Q" or "V"
. => single char wildcard; matches ALL vars
Many of the above patterns can be combined to create more
complex filters, for example
^(goph|serv)|[_]{2,3}|(addr|name)$
matches vars with any of the following characteristics:
- begins w/ "GOPH" or "SERV"
- contains 2 or 3 "_" chars
- ends w/ "ADDR" or "NAME"
(Q) Anything else?
(A) Life can be is a tenuous thing so step away from the keyboard
whenever you can, while you can: it's later than you think.
