dc - Linux Command Dc may be invoked with the following command-line options: -V --version Print out the version of dc

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1 - CentOS Linux Uses Guide - Linux Command SYNOPSIS [-V] [--vesion] [-h] [--help] [-e sciptexpession] [--expession=sciptexpession] [-f sciptfile] [--file=sciptfile] [file...] DESCRIPTION is a evese-polish desk calculato which suppots unlimited peci- sion aithmetic. It also allows you to define and call macos. No- mally eads fom the standad input; if any command aguments ae given to it, they ae filenames, and eads and executes the contents of the files befoe eading fom standad input. All nomal output is to standad output; all eo output is to standad eo. A evese-polish calculato stoes numbes on a stack. Enteing a num- be pushes it on the stack. Aithmetic opeations pop aguments off the stack and push the esults. To ente a numbe in, type the digits with an optional decimal point. Exponential notation is not suppoted. To ente a negative numbe, begin the numbe with â â _â â. â â -â â cannot be used fo this, as it is a binay opeato fo subtaction instead. To ente two numbes in succession, sepaate them with spaces o newlines. These have no meaning as commands. OPTIONS may be invoked with the following command-line options: -V --vesion Pint out the vesion of that is being un and a copyight -h notice, then exit. --help Pint a usage message biefly summaizing these command-line bug-epoting addess, then exit. -e scipt options and the --expession= / 7

2 - CentOS Linux Uses Guide scipt Add the commands in scipt to the set of commands to be un -f scipt-file while pocessing the input. --file= scipt-file Add the commands contained in the file scipt-file to the set of commands to be un while pocessing the input. If any command-line paametes emain afte pocessing the above, these out as a "base (UCHAR_MAX+)" byte steam. Assuming that (UCHAR_MAX+) is 256 (as it is on most machines with 8-bit bytes), the sequence KSK 0k/ [_*]sx d0>x [256~aPd0<x]dsxx sxlkk could also accomplish this function, except fo the side- effect of clobbeing the x egiste. f Pints the entie contents of the stack without alteing any- thing. This is a good command to use if you ae lost o want to figue out what the effect of some command has been. Aithmetic + Pops two values off the stack, adds them, and pushes the esult. The pecision of the esult is detemined only by the values of the aguments, and is enough to be exact. - Pops two values, subtacts the fist one popped fom the second one popped, and pushes the esult. * Pops two values, multiplies them, and pushes the esult. The numbe of faction digits in the esult depends on the cuent pecision value and the numbe of faction digits in the two aguments. / Pops two values, divides the second one popped fom the fist one popped, and pushes the esult. The numbe of faction dig- its is specified by the pecision value. 2 / 7

3 - CentOS Linux Uses Guide % Pops two values, computes the emainde of the division that the / command would do, and pushes that. The value computed is the same as that computed by the sequence Sd dld/ Ld*-. ~ Pops two values, divides the second one popped fom the fist one popped. The quotient is pushed fist, and the emainde is pushed next. The numbe of faction digits used in the division is specified by the pecision value. (The sequence SdSn lnld/ LnLd% could also accomplish this function, with slightly diffe- ent eo checking.) ^ Pops two values and exponentiates, using the fist value popped as the exponent and the second popped as the base. The faction pat of the exponent is ignoed. The pecision value specifies the numbe of faction digits in the esult. Pops thee values and computes a modula exponentiation. The fist value popped is used as the eduction modulus; this value must be a non-zeo numbe, and should be an intege. The second popped is used as the exponent; this value must be a non-nega- tive numbe, and any factional pat of this exponent will be ignoed. The thid value popped is the base which gets exponen- tiated, which should be an intege. Fo small integes this is like the sequence Sm^Lm%, but, unlike ^, this command will wok with abitaily lage exponents. copy of it. Thus, â â 4d*pâ â computes 4 squaed and pints it. Reveses the ode of (swaps) the top two values on the stack. Registes povides at least 256 memoy egistes, each named by a single chaa numbe o a sting in a egiste and etieve it late. s Pop the value off the top of the stack and stoe it into egis- te acte. You can stoe 3 / 7

4 - CentOS Linux Uses Guide. l Copy the value in egiste and push it onto the stack. This does not alte the contents of. Each egiste also contains its own stack. The cuent egiste value is the top of the egisteâ s stack. S Pop the value off the top of the (main) stack and push it onto the stack of egiste. The pevious value of the egiste becomes inaccessible. L Pop the value off the top of egiste â s stack and push it onto the main stack. The pevious value in egiste â s stack, if any, is now accessible via the l command. Paametes has thee paametes that contol its opeation: the pecision, the input adix, and the output adix. The pecision specifies the numbe of faction digits to keep in the esult of most aithmetic opeations. The input adix contols the intepetation of numbes typed in; all numbes typed in use this adix. The output adix is used fo pinting numbes. The input and output adices ae sepaate paametes; you can make them unequal, which can be useful o confusing. The input adix must be between 2 and 6 inclusive. The output adix must be at least 2. The pecision must be zeo o geate. The pecision is always measued in decimal digits, egadless of the cuent input o output adix. i Pops the value off the top of the stack and uses it to set the input adix. o Pops the value off the top of the stack and uses it to set the output adix. k Pops the value off the top of the stack and uses it to set the pecision. I Pushes the cuent input adix on the stack. O 4 / 7

5 - CentOS Linux Uses Guide Pushes the cuent output adix on the stack. [ chaactes ] Makes a sting containing chaactes (contained between balanced [ and ] chaactes), and pushes it on the stack. Fo example, [foo]p pints the chaactes foo (with no newline). a The top-of-stack is popped. If it was a numbe, then the low- ode byte of this numbe is conveted into a sting and pushed onto the stack. Othewise the top-of-stack was a sting, and the fist chaacte of that sting is pushed back. x Pops a value off the stack and executes it as a maco. Nomally it should be a sting; if it is a numbe, it is simply pushed back onto the stack. Fo example, [p]x executes the maco p which pushes on the stack and pints on a sepaate line. Macos ae most often stoed in egistes; [p]sa stoes a maco to pint into egiste a, and lax invokes this maco. > Pops two values off the stack and compaes them assuming they ae numbes, executing the contents of egiste as a maco if the oiginal top-of-stack is geate. Thus, 2>a 5 / 7

6 - CentOS Linux Uses Guide will invoke egiste a â s contents and 2 >a will not.!> Simila but invokes the maco if the oiginal top-of-stack is not geate than (less than o equal to) what was the second-to- top. < Simila but invokes the maco if the oiginal top-of-stack is less.!< Simila but invokes the maco if the oiginal top-of-stack is not less than (geate than o equal to) what was the second-to- top. = Simila but invokes the maco if the two numbes popped ae equal.!= Simila but invokes the maco if the two numbes popped ae not equal.? Reads a line fom the teminal and executes it. This command allows a maco to equest input fom the use. q exits fom a maco and also fom the maco which invoked it. If called fom the top level, o fom a maco which was called diectly fom the top level, the q command will cause to exit. Q Pops a value off the stack and uses it as a count of levels of maco execution to be exited. Thus, 3Q exits thee levels. The Q command will neve cause to exit. pasing of the!<,!=, and!> commands take pecedence, so if you want to un a command stating with <, =, o > you will need to add a space afte the!. # Will intepet the est of the line as a comment. 6 / 7

7 - CentOS Linux Uses Guide : Will pop the top two values off of the stack. The old second- to-top value will be stoed in the aay, indexed by the old top-of-stack value. ; Pops the top-of-stack and uses it as an index into the aay. The selected value is then pushed onto the stack. Note that each stacked instance of a egiste has its own aay associ- ated with it. Thus 0:a 0Sa 2 0:a La 0;ap will pint, because the 2 was stoed in an instance of 0:a that was late popped. BUGS bug epots to bug-@gnu.og. GNU Poject DC() Linux Help documents. These manual pages will also wok fo Red Hat 5.2 Man() output conveted with man2html Joomla SEO poweed by JoomSEF 7 / 7