Beginning Portable Shell Scripting: From Novice to Professional

CHAPTER 8Utility Portability

This chapter discusses the portability of programs external to the shell. Most shell scripts need to use a number of programs other than the shell itself to achieve their ends. Compared to the divergence in the functions and options offered by utilities, the variance of all the shell languages is relatively trivial.

This chapter does not attempt to provide a complete or comprehensive list of differences between different utilities; such a list would be much larger than this book. A shell script may have access to hundreds, or even thousands, of distinct programs. Many programs exist in three or more distinct variants with different sets of options, different names for the same options, and other sources of confusion. ...