POSIX Is a Specification, Not a Shell: Why Portability Is More Complicated Than It Seems
This article argues that "POSIX shell" is a misnomer — POSIX is a specification, not a program. The author demonstrates through examples (like echo "C:\new") that different shell implementations (bash, dash, ksh, yash, ash) handle the same POSIX-specified code differently due to gaps, extensions, and historical quirks. The piece highlights the practical pitf
