diff options
Diffstat (limited to 'manuals/dc/EHN.1')
| -rw-r--r-- | manuals/dc/EHN.1 | 45 |
1 files changed, 6 insertions, 39 deletions
diff --git a/manuals/dc/EHN.1 b/manuals/dc/EHN.1 index efeb0bbaecf9..5df155cf5253 100644 --- a/manuals/dc/EHN.1 +++ b/manuals/dc/EHN.1 @@ -29,10 +29,8 @@ .nh .ad l .SH Name -.PP dc - arbitrary-precision decimal reverse-Polish notation calculator .SH SYNOPSIS -.PP \f[B]dc\f[R] [\f[B]-cChiPRvVx\f[R]] [\f[B]--version\f[R]] [\f[B]--help\f[R]] [\f[B]--digit-clamp\f[R]] [\f[B]--no-digit-clamp\f[R]] [\f[B]--interactive\f[R]] @@ -43,7 +41,6 @@ dc - arbitrary-precision decimal reverse-Polish notation calculator [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION -.PP dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. @@ -60,7 +57,6 @@ For example, if a user wants the \f[B]scale\f[R] always set to \f[B]10\f[R], they can set \f[B]DC_ENV_ARGS\f[R] to \f[B]-e 10k\f[R], and this dc(1) will always start with a \f[B]scale\f[R] of \f[B]10\f[R]. .SH OPTIONS -.PP The following are the options that dc(1) accepts. .TP \f[B]-C\f[R], \f[B]--no-digit-clamp\f[R] @@ -261,7 +257,6 @@ This is a \f[B]non-portable extension\f[R]. .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN -.PP If no files are given on the command-line and no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then dc(1) reads from \f[B]stdin\f[R]. @@ -274,7 +269,6 @@ ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. .SH STDOUT -.PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output @@ -283,7 +277,7 @@ to \f[B]stdout\f[R]. \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in -\f[B]dc >&-\f[R], it will quit with an error. +\f[B]dc >&-\f[R], it will quit with an error. This is done so that dc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP @@ -291,13 +285,12 @@ If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR -.PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in -\f[B]dc 2>&-\f[R], it will quit with an error. +\f[B]dc 2>&-\f[R], it will quit with an error. This is done so that dc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP @@ -305,7 +298,6 @@ If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX -.PP Each item in the input source code, either a number (see the \f[B]NUMBERS\f[R] section) or a command (see the \f[B]COMMANDS\f[R] section), is processed and executed, in order. @@ -340,11 +332,9 @@ precision of any operations (with exceptions). The max allowable value for \f[B]scale\f[R] can be queried in dc(1) programs with the \f[B]V\f[R] command. .SS Comments -.PP Comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SH NUMBERS -.PP Numbers are strings made up of digits, uppercase letters up to \f[B]F\f[R], and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]DC_NUM_MAX\f[R] digits. @@ -391,10 +381,8 @@ value of \f[B]ibase\f[R]. If clamping is on, and the clamped value of a character is needed, use a leading zero, i.e., for \f[B]A\f[R], use \f[B]0A\f[R]. .SH COMMANDS -.PP The valid commands are listed below. .SS Printing -.PP These commands are used for printing. .TP \f[B]p\f[R] @@ -431,7 +419,6 @@ without altering anything. Users should use this command when they get lost. .RE .SS Arithmetic -.PP These are the commands used for arithmetic. .TP \f[B]+\f[R] @@ -621,7 +608,6 @@ a short-circuit operator. This is a \f[B]non-portable extension\f[R]. .RE .SS Stack Control -.PP These commands control the stack. .TP \f[B]c\f[R] @@ -637,7 +623,6 @@ Swaps (\[lq]reverses\[rq]) the two top items on the stack. \f[B]R\f[R] Pops (\[lq]removes\[rq]) the top value from the stack. .SS Register Control -.PP These commands control registers (see the \f[B]REGISTERS\f[R] section). .TP \f[B]s\f[R]\f[I]r\f[R] @@ -659,7 +644,6 @@ push it onto the main stack. The previous value in the stack for register \f[I]r\f[R], if any, is now accessible via the \f[B]l\f[R]\f[I]r\f[R] command. .SS Parameters -.PP These commands control the values of \f[B]ibase\f[R], \f[B]obase\f[R], and \f[B]scale\f[R]. Also see the \f[B]SYNTAX\f[R] section. @@ -726,7 +710,6 @@ stack. This is a \f[B]non-portable extension\f[R]. .RE .SS Strings -.PP The following commands control strings. .PP dc(1) can work with both numbers and strings, and registers (see the @@ -943,7 +926,6 @@ to make dc(1) exit with the \f[B]Q\f[R] command, so the sequence This is a \f[B]non-portable extension\f[R]. .RE .SS Status -.PP These commands query status of the stack or its top value. .TP \f[B]Z\f[R] @@ -1004,7 +986,6 @@ This means that this command will never push \f[B]0\f[R]. This is a \f[B]non-portable extension\f[R]. .RE .SS Arrays -.PP These commands manipulate arrays. .TP \f[B]:\f[R]\f[I]r\f[R] @@ -1024,7 +1005,6 @@ Pushes the length of the array \f[I]r\f[R] onto the stack. This is a \f[B]non-portable extension\f[R]. .RE .SS Global Settings -.PP These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter \f[B]g\f[R]. @@ -1047,7 +1027,6 @@ Pushes \f[B]0\f[R] onto the stack if the leading zero setting has not been enabled with the \f[B]-z\f[R] or \f[B]--leading-zeroes\f[R] options (see the \f[B]OPTIONS\f[R] section), non-zero otherwise. .SH REGISTERS -.PP Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) .PP @@ -1063,7 +1042,6 @@ The only exceptions are: a newline (\f[B]`\[rs]n'\f[R]) and a left bracket (\f[B]`['\f[R]); it is a parse error for a newline or a left bracket to be used as a register name. .SS Extended Register Mode -.PP Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. .PP @@ -1078,7 +1056,6 @@ In that case, the register name is found according to the regex \f[B][a-z][a-z0-9_]*\f[R] (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. .SH RESET -.PP When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. @@ -1095,7 +1072,6 @@ Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .SH PERFORMANCE -.PP Most dc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This dc(1) does something different. @@ -1115,7 +1091,6 @@ checking. This integer type depends on the value of \f[B]DC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS -.PP The following are the limits on dc(1): .TP \f[B]DC_LONG_BIT\f[R] @@ -1177,7 +1152,6 @@ large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES -.PP As \f[B]non-portable extensions\f[R], dc(1) recognizes the following environment variables: .TP @@ -1300,7 +1274,6 @@ This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .SH EXIT STATUS -.PP dc(1) returns the following exit statuses: .TP \f[B]0\f[R] @@ -1367,7 +1340,6 @@ These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE -.PP Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag @@ -1380,7 +1352,6 @@ dc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE -.PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some @@ -1404,7 +1375,6 @@ required in the bc(1) specification (see the \f[B]STANDARDS\f[R] section), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Prompt -.PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]DC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] @@ -1425,7 +1395,6 @@ and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING -.PP Sending a \f[B]SIGINT\f[R] will cause dc(1) to do one of two things. .PP If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] @@ -1457,19 +1426,17 @@ the user to continue. \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause dc(1) to clean up and exit, and it uses the default handler for all other signals. .SH SEE ALSO -.PP bc(1) .SH STANDARDS -.PP The dc(1) utility operators and some behavior are compliant with the operators in the IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) bc(1) specification at https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html . .SH BUGS -.PP None are known. Report bugs at https://git.gavinhoward.com/gavin/bc . .SH AUTHOR -.PP -Gavin D. -Howard <gavin@gavinhoward.com> and contributors. +Gavin D. Howard \c +.MT gavin@gavinhoward.com +.ME \c +\ and contributors. |