All currently-maintained UNIX/Linux Operating Systems have a POSIX-compliant
/bin/sh. If you want to write shell scripts that run on any UNIX/Linux system, this is the book for you.
This book will push the boundaries of your knowledge of UNIX/Linux scripting by introducing techniques to overcome the most daunting tasks. Issues once thought to be too complex for shell programming are tackled in-depth and in a cross-platform compatible nature.
While there are many shells in the UNIX/Linux world, this book focuses on POSIX-compliant Bourne Shell for best portability. POSIX shell is well supported on (to name a few) FreeBSD, NetBSD, Solaris, and Linux including RedHat, CentOS, Ubuntu, and a great many more.
Techniques specific to other shells such as Bourne Again Shell (bash) are avoided, allowing you to write code targeting more platforms with fewer dependencies.
Other programming languages may offer more built-in features, but POSIX shell provides everything required. Things like substrings, arrays, structs, floating-point arithmetic, and much more will be presented in the following chapters.