INNOVATIONS THAT CAN IMPROVE SHELL SCRIPT

For repetitive functions in Unix flavors in Unix flavors, shell scripts are a major time saver as a Unix asset. Though shell scripts do give the intended result. Time is one of the limitations that a production environment may face especially when faced with huge files.

One ay of improving Bash Shell scripts for example is by the use of Dialog. One can try to download the cdialog-0.9 from Linux shell directory or get it from reliable Linux distributors.

When running shell script commands an interactive shell script comes in handy when one wants to take control of the program at run-time. A practical approach to this would be use of the Dialogue command when drawing text-mode colored windows that have different menus e.g. message boxes etc. The script behavior can even be modified through the use of input from the user.

Shell programming has had its efficiency improved with use of Bash Dynamicably Loadabe. Under this operation, the dynamically loadable commands (built-in) are utilized for this task. Starting new processes, whether command substitutions or external commands generate sluggish scripts in almost all cases. Polya (1973, p. 67) explains that when using Bourne shell one relies on external commands in order to perform operations. Expr and awk are normally used ofr calculations, while the commands to manipulate strings are expr, basename etc.

Use of Korn, string chopping, integer arithmetic, POSIX/SUS standardization, made writing of programs without the calling in external commands likely, though some external commands such as converting uppercase letters to lower case demanded still external commands. With bash, at run time commands are compiled and loaded when necessary. With bash built in commands such as strftime, one is able to attempt without utilizing external commands arithmetic operations. For short string conversion, the shell function operates well though for words that are long it tends to be slow and thus the tr execution time is almost encroached. Built in commands come in handy under these circumstances for they are able to amalgamate many commands into a single operation which is more time saving.

It is observed generally that, in a shell script, each code line takes time to execute. For example, the monte carlo (Bourne) method for Pi, outlines how the value of a byte is arrived at in several ways. When written purely on a shell approach, due to the number of loops required, the version becomes painstakingly slow. Ramey and Fox (2003, p. 112) observe that if one would like to optimize performance, the use of an external utility that is written in a language that is complied is the best option. The heavy lifting can be performed by the Perl or awk interpreter. Though the above not being compiled languages, they have compiled routines.

Super Shell Indent is another innovation that has improved shell scripting, by improving its indentation. It calculates the level of indent founded on the syntax pairs of begin/end contrary to pattern matching or complex conditionals.

One can also try to write their shell scripts in Haskell. When installing it one is bound to observe much of the shell scripting initially, though when scripting specifically for a Haskell project, use of Haskell with a shell library the combination result is quite satisfactory