The shell is a command programming language that provides an interface to the UNIX operating system. Its features include control-flow primitives, parameter passing, variables and string substitution. Constructs such as while, if then else, case and for are available. Two-way communication is possible between the shell and commands. String-valued parameters, typically file names or flags, may be passed to a command. A return code is set by commands that may be used to determine control-flow, and the standard output from a command may be used as shell input.

The MS batch file offers similar functional possibilities but has different syntax and fewer functions. Because of these differences, managing the project applications across platforms may be tricky using shell/batch approach.

PERL is the best candidate to replace shell and batch scripts. PERL offers scripting techniques which cover all the imaginary possibilities of shells and batch files, plus enhanced and powerful text processing of input/output data. PERL scripts execute very fast. These scripts can work together with Makefiles giving incredible power of options to build sophisticated projects.