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GNU bc version 1.06: Extra configuration options: --with-readline tells bc to use the readline package that allows for editing input lines when run interactive. --with-editline tells bc to use the BSD editline package that allows for editing input lines when run interactive. Extra make steps: The simple make compiles a version of bc with fixed parameters for the recursive multiplication algorithm. The fixed parameter is the number of digits where a sequential algorithm is used instead of the recursive algorithm. It is set to a value that is known good on a couple of machines. (Sparc Ultra 10, Pentium II, 450.) I'm calling this point the crossover point. To make a version of bc with a custom crossover point for your machine, do the following steps: make timetest make The timetest step takes a minimum of 10 minutes to complete. -------- Original comp.sources.reviewed README -------- Program: GNU bc Author: Philip A. Nelson E-mail: phil@cs.wwu.edu OS: UNIX (BSD, System V, MINIX, POSIX) Copying: GNU GPL version 2 Copyright holder: Free Software Foundation, Inc. Version: bc version 1.01 Required: vsprintf and vfprintf routines. Machines: It has been compiled and run on the following environments: BSD4.3 (VAX 11) MINIX 1.5 (IBM PC, both K&R and ANSI compilers) MINIX 1.5 (pc532) SUN-OS 4.1 (SUN 3 and SUN 4) SVR3V5 (Motorola 68K) SVR3.2 (3B2) SVR4.0.2 (a 386 box) ULTRIX 4.1 (DEC 5000) UTS (Amdahl) bc is an arbitrary precision numeric processing language. Syntax is similar to C, but differs in many substantial areas. It supports interactive execution of statements. bc is a utility included in the POSIX P1003.2/D11 draft standard. This version was written to be a POSIX compliant bc processor with several extensions to the draft standard. Option flags are available to cause warning or rejection of the extensions to the POSIX standard. For those who want only POSIX bc with no extensions, a grammar is provided for exactly the language described in the POSIX document. The grammar (sbc.y) comes from the POSIX document. The Makefile contains rules to make sbc. (for Standard BC) Since the POSIX document does not specify how bc must be implemented, this version does not use the historical method of having bc be a compiler for the dc calculator. This version has a single executable that both compiles the language and runs the a resulting "byte code". The "byte code" is NOT the dc language. Also, included in the initial distribution is the library file vfprintf.c for MINIX systems. My minix 1.5 did not have this file. Also, you should verify that vsprintf.c works correctly on your system. The extensions add some features I think are missing. The major changes and additions for bc are (a) names are allowed to be full identifiers ([a-z][a-z0-9_]*), (b) addition of the &&, ||, and ! operators, (c) allowing comparison and boolean operations in any expression, (d) addition of an else clause to the if statement, (e) addition of a new standard function "read()" that reads a number from the standard input under program control, (f) passing of arrays as parameters by variable, (g) addition of the "halt" statement that is an executable statement unlike the quit (i.e. "if (1 == 0) quit" will halt bc but "if (1 == 0) halt" will not halt bc.), and (h) the addition of the special variable "last" that is assigned the value of each print as the number is printed. -----------------------------------------------------------------------