# HG changeset patch # User meillo@marmaro.de # Date 1266770003 -3600 # Node ID 00e306ee903b040ec8af1dae42dc526672227ff3 # Parent 59305c854751408c9589073121c2bd36b0cc284c reformated content (ch03) diff -r 59305c854751 -r 00e306ee903b unix-phil.ms --- a/unix-phil.ms Sun Feb 21 17:23:19 2010 +0100 +++ b/unix-phil.ms Sun Feb 21 17:33:23 2010 +0100 @@ -561,16 +561,19 @@ is the one that survives. (This may be at the level of one creature, or at the level of one species.) The fitness of software is affected mainly by four properties: -.IP \(bu -portability of code -.IP \(bu -portability of data -.IP \(bu -range of usability -.IP \(bu -reuseability of parts +portability of code, portability of data, range of usability, and reusability of parts. +.\" .IP \(bu +.\" portability of code +.\" .IP \(bu +.\" portability of data +.\" .IP \(bu +.\" range of usability +.\" .IP \(bu +.\" reuseability of parts .PP -Portability of code means, using high-level programming languages, +(1) +.I "Portability of code +means, using high-level programming languages, sticking to the standard, and avoiding optimizations that introduce dependencies on specific hardware. Hardware has a much lower lifetime than software. @@ -580,7 +583,9 @@ adaption is the key to success. .\" cf. practice of prog: ch08 .PP -Portability of data is best achieved by avoiding binary representations +(2) +.I "Portability of data +is best achieved by avoiding binary representations to store data, because binary representations differ from machine to machine. Textual represenation is favored. Historically, ASCII was the charset of choice. @@ -592,7 +597,10 @@ to directly edit it with text editors and other tools from the Unix toolchest. .\" gancarz tenet 5 .PP -A large range of usability ensures good adaption, and thus good survival. +(3) +A large +.I "range of usability +ensures good adaption, and thus good survival. It is a special distinction if a software becomes used in fields of action, the original authors did never imagine. Software that solves problems in a general way will likely be used @@ -615,7 +623,9 @@ .LP Successful software adopts itself to the changing world. .PP -Reuse of parts is even one step further. +(4) +.I "Reuse of parts +is even one step further. A software may completely lose its field of action, but parts of which the software is build may be general and independent enough to survive this death.