POSIX compliance in no way makes environmental variables in shell scripting more usable and readable, its usually the opposite.
I say this as somebody who has written shell scripts for almost 20 years.
Constructs like
if [ "X${str1}" = "X${str2}" ]
to avoid things exploding because a zero length variable might exist is a stupid and ugly hack.
Not to mention the hell that is trying to use a user supplied filename safely in shellscript. (for the uninitiated, a unix filename can contain any character, and any sequence of bytes besides / and 0x00, including newlines, backspaces, shell meta-charachters and so many more exciting things)
I say this as somebody who has written shell scripts for almost 20 years.
Constructs like
to avoid things exploding because a zero length variable might exist is a stupid and ugly hack.Not to mention the hell that is trying to use a user supplied filename safely in shellscript. (for the uninitiated, a unix filename can contain any character, and any sequence of bytes besides / and 0x00, including newlines, backspaces, shell meta-charachters and so many more exciting things)