In the beginning was FoilTeX… I started using LaTeX around 1995. For making slides1 I initially used FoilTeX, briefly switched to prosper around 2004 (I'm pretty sure I also tried powerdot at some point) before going back to FoilTeX, but with a custom myfoils.sty style file supposed to allow a lighter and more convenient markup: a slide environment, abbreviations for very common markup: \bi \ei \i for itemizes, \be \ee for enumerate, \bmp \emp for a minipage, \img for including a picture.

As explained in this post I wanted to patch a symbol in a binary file, and for that needed to echo a specific byte value (xEA) into a sed command appearing in a Makefile recipe. Now, you may be aware that the echo command lives in /bin/, but the shell also provide an echo shell builtin. Let's see how we can echo a byte with hex value EA in both cases: