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Fix some formatting issues with bc man page 

* Space at end of lines removed
* Removed or added word space
* Use "\(en" as a dash to indicate a range instead of "-"
* Added "\&" after a full stop if it is not an end of sentence
* Use "\e" to print a backslash
* Use either macros "IR" or "RI" when mixing these two styles in a row of
  words
* Use "\," when mixing roman and italic, "\/" for italic and roman.
* The Word 'funtion' changed to 'function'.
Bug-Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=725898
Forwarded: no

Gbp-Pq: Name 07_bc_man.diff
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Bjarni Ingi Gislason 2022-08-15 16:25:12 +08:00 committed by Lu zhiping
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commit db58bce935
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@ -36,7 +36,7 @@ bc - An arbitrary precision calculator language
.SH DESCRIPTION
\fBbc\fR is a language that supports arbitrary precision numbers
with interactive execution of statements. There are some similarities
in the syntax to the C programming language.
in the syntax to the C programming language.
A standard math library is available by command line option.
If requested, the math library is defined before processing any files.
\fBbc\fR starts by processing code from all the files listed
@ -47,8 +47,8 @@ processor, \fBbc\fR will never read from the standard input.)
.PP
This version of \fBbc\fR contains several extensions beyond
traditional \fBbc\fR implementations and the POSIX draft standard.
Command line options can cause these extensions to print a warning
or to be rejected. This
Command line options can cause these extensions to print a warning
or to be rejected. This
document describes the language accepted by this processor.
Extensions will be identified as such.
.SS OPTIONS
@ -87,13 +87,13 @@ Numbers are stored in two types of variables, simple variables and
arrays. Both simple variables and array variables are named. Names
begin with a letter followed by any number of letters, digits and
underscores. All letters must be lower case. (Full alpha-numeric
names are an extension. In POSIX \fBbc\fR all names are a single
names are an extension. In POSIX \fBbc\fR all names are a single
lower case letter.) The type of variable is clear by the context
because all array variable names will be followed by brackets ([]).
.PP
There are four special variables, \fBscale, ibase, obase,\fR and
\fBlast\fR. \fBscale\fR defines how some operations use digits after the
decimal point. The default value of \fBscale\fR is 0. \fBibase\fR
decimal point. The default value of \fBscale\fR is 0. \fBibase\fR
and \fBobase\fR define the conversion base for input and output
numbers. The default for both input and output is base 10.
\fBlast\fR (an extension) is a variable that has the value of the last
@ -125,7 +125,7 @@ by the variable \fBibase\fR. (There is an exception in functions.)
The legal values of \fBibase\fR are 2 through 36. (Bases greater than
16 are an extension.) Assigning a value outside this range to
\fBibase\fR will result in a value of 2 or 36. Input numbers may
contain the characters 0-9 and A-Z. (Note: They must be capitals.
contain the characters 0\(en9 and A\(enZ. (Note: They must be capitals.
Lower case letters are variable names.) Single digit numbers always
have the value of the digit regardless of the value of
\fBibase\fR. (i.e. A = 10.) For multi-digit numbers, \fBbc\fR changes
@ -149,7 +149,8 @@ A simple variable is just a
.RE
and an array variable is specified as
.RS
\fIname\fR[\fIexpr\fR]
.\"\fIname\fR[\fIexpr\fR]
.IR name [ expr ]
.RE
Unless specifically
mentioned the scale of the result is the maximum scale of the
@ -187,13 +188,13 @@ to zero and both expressions are integers this expression is the
integer remainder function.
.IP "expr ^ expr"
The result of the expression is the value of the first raised to the
second. The second expression must be an integer. (If the second
second. The second expression must be an integer. (If the second
expression is not an integer, a warning is generated and the
expression is truncated to get an integer value.) The scale of the
result is \fBscale\fR if the exponent is negative. If the exponent
is positive the scale of the result is the minimum of the scale of the
first expression times the value of the exponent and the maximum of
\fBscale\fR and the scale of the first expression. (e.g. scale(a^b)
\fBscale\fR and the scale of the first expression. (e.g.\& scale(a^b)
= min(scale(a)*b, max( \fBscale,\fR scale(a))).) It should be noted
that expr^0 will always return the value of 1.
.IP "( expr )"
@ -226,7 +227,7 @@ The result is 1 if expr1 is equal to expr2.
The result is 1 if expr1 is not equal to expr2.
.PP
Boolean operations are also legal. (POSIX \fBbc\fR does NOT have
boolean operations). The result of all boolean operations are 0 and 1
boolean operations). The result of all boolean operations are 0 and 1
(for false and true) as in relational expressions. The boolean
operators are:
.IP "!expr"
@ -253,7 +254,7 @@ unary - operator, nonassociative
.fi
.PP
This precedence was chosen so that POSIX compliant \fBbc\fR programs
will run correctly. This will cause the use of the relational and
will run correctly. This will cause the use of the relational and
logical operators to have some unusual behavior when used with
assignment expressions. Consider the expression:
.RS
@ -268,7 +269,7 @@ with the assignment operators.
.PP
There are a few more special expressions that are provided in \fBbc\fR.
These have to do with user defined functions and standard
functions. They all appear as "\fIname\fB(\fIparameters\fB)\fR".
functions. They all appear as "\,\fIname\/\fB(\,\fIparameters\/\fB)\fR".
See the section on functions for user defined functions. The standard
functions are:
.IP "length ( expression )"
@ -281,7 +282,7 @@ cause problems with the mixing of data and program in the standard input.
The best use for this function is in a previously written program that
needs input from the user, but never allows program code to be input
from the user. The value of the read function is the number read from
the standard input using the current value of the variable
the standard input using the current value of the variable
\fBibase\fR for the conversion base.
.IP "scale ( expression )"
The value of the scale function is the number of digits after the decimal
@ -294,7 +295,7 @@ Statements (as in most algebraic languages) provide the sequencing of
expression evaluation. In \fBbc\fR statements are executed "as soon
as possible." Execution happens when a newline in encountered and
there is one or more complete statements. Due to this immediate
execution, newlines are very important in \fBbc\fR. In fact, both a
execution, newlines are very important in \fBbc\fR. In fact, both a
semicolon and a newline are used as statement separators. An
improperly placed newline will cause a syntax error. Because newlines
are statement separators, it is possible to hide a newline by using
@ -312,7 +313,7 @@ expression is evaluated and printed to the output. After the number
is printed, a newline is printed. For example, "a=1" is an assignment
statement and "(a=1)" is an expression that has an embedded
assignment. All numbers that are printed are printed in the base
specified by the variable \fBobase\fR. The legal values for \fB
specified by the variable \fBobase\fR. The legal values for \fB
obase\fR are 2 through BC_BASE_MAX. (See the section LIMITS.) For
bases 2 through 16, the usual method of writing numbers is used. For
bases greater than 16, \fBbc\fR uses a multi-character digit method
@ -325,13 +326,13 @@ These long numbers will be split across lines using the "\e" as the
last character on a line. The maximum number of characters printed
per line is 70. Due to the interactive nature of \fBbc\fR, printing
a number causes the side effect of assigning the printed value to the
special variable \fBlast\fR. This allows the user to recover the
special variable \fBlast\fR. This allows the user to recover the
last value printed without having to retype the expression that
printed the number. Assigning to \fBlast\fR is legal and will
overwrite the last printed value with the assigned value. The newly
assigned value will remain until the next number is printed or another
value is assigned to \fBlast\fR. (Some installations may allow the
use of a single period (.) which is not part of a number as a short
value is assigned to \fBlast\fR. (Some installations may allow the
use of a single period (.\&) which is not part of a number as a short
hand notation for for \fBlast\fR.)
.IP "string"
The string is printed to the output. Strings start with a double quote
@ -343,13 +344,13 @@ The print statement (an extension) provides another method of output.
The "list" is a list of strings and expressions separated by commas.
Each string or expression is printed in the order of the list. No
terminating newline is printed. Expressions are evaluated and their
value is printed and assigned to the variable \fBlast\fR. Strings
value is printed and assigned to the variable \fBlast\fR. Strings
in the print statement are printed to the output and may contain
special characters. Special characters start with the backslash
character (\e). The special characters recognized by \fBbc\fR are
"a" (alert or bell), "b" (backspace), "f" (form feed), "n" (newline),
"r" (carriage return), "q" (double quote), "t" (tab), and "\e" (backslash).
Any other character following the backslash will be ignored.
Any other character following the backslash will be ignored.
.IP "{ statement_list }"
This is the compound statement. It allows multiple statements to be
grouped together for execution.
@ -365,7 +366,7 @@ is non-zero. It evaluates the expression before each execution of
the statement. Termination of the loop is caused by a zero
expression value or the execution of a break statement.
.IP "\fBfor\fR ( [expression1] ; [expression2] ; [expression3] ) statement"
The for statement controls repeated execution of the statement.
The for statement controls repeated execution of the statement.
Expression1 is evaluated before the loop. Expression2 is evaluated
before each execution of the statement. If it is non-zero, the statement
is evaluated. If it is zero, the loop is terminated. After each
@ -374,7 +375,7 @@ of expression2. If expression1 or expression3 are missing, nothing is
evaluated at the point they would be evaluated.
If expression2 is missing, it is the same as substituting
the value 1 for expression2. (The optional expressions are an
extension. POSIX \fBbc\fR requires all three expressions.)
extension. POSIX \fBbc\fR requires all three expressions.)
The following is equivalent code for the for statement:
.nf
.RS
@ -389,7 +390,7 @@ while (expression2) {
This statement causes a forced exit of the most recent enclosing while
statement or for statement.
.IP "\fBcontinue\fR"
The continue statement (an extension) causes the most recent enclosing
The continue statement (an extension) causes the most recent enclosing
for statement to start the next iteration.
.IP "\fBhalt\fR"
The halt statement (an extension) is an executed statement that causes
@ -399,7 +400,7 @@ not executed.
.IP "\fBreturn\fR"
Return the value 0 from a function. (See the section on functions.)
.IP "\fBreturn\fR ( expression )"
Return the value of the expression from a function. (See the section on
Return the value of the expression from a function. (See the section on
functions.) As an extension, the parenthesis are not required.
.SS PSEUDO STATEMENTS
These statements are not statements in the traditional sense. They are
@ -415,7 +416,7 @@ example, "if (0 == 1) quit" will cause \fBbc\fR to terminate.
Print a longer warranty notice. This is an extension.
.SS FUNCTIONS
Functions provide a method of defining a computation that can be executed
later. Functions in
later. Functions in
.B bc
always compute a value and return it to the caller. Function definitions
are "dynamic" in the sense that a function is undefined until a definition
@ -429,13 +430,13 @@ then replaces the older definition. A function is defined as follows:
.RE
.fi
A function call is just an expression of the form
"\fIname\fB(\fIparameters\fB)\fR".
"\,\fIname\/\fB(\,\fIparameters\/\fB)\fR".
.PP
Parameters are numbers or arrays (an extension). In the function definition,
zero or more parameters are defined by listing their names separated by
commas. All parameters are call by value parameters.
commas. All parameters are call by value parameters.
Arrays are specified in the parameter definition by
the notation "\fIname\fB[]\fR". In the function call, actual parameters
the notation "\,\fIname\/\fB[]\fR". In the function call, actual parameters
are full expressions for number parameters. The same notation is used
for passing arrays as for defining array parameters. The named array is
passed by value to the function. Since function definitions are dynamic,
@ -464,7 +465,7 @@ The function body is a list of \fBbc\fR statements. Again, statements
are separated by semicolons or newlines. Return statements cause the
termination of a function and the return of a value. There are two
versions of the return statement. The first form, "\fBreturn\fR", returns
the value 0 to the calling expression. The second form,
the value 0 to the calling expression. The second form,
"\fBreturn ( \fIexpression \fB)\fR", computes the value of the expression
and returns that value to the calling expression. There is an implied
"\fBreturn (0)\fR" at the end of every function. This allows a function
@ -494,7 +495,7 @@ define d (n)
.fi
.PP
Functions may be defined as \fBvoid\fR. A void
funtion returns no value and thus may not be used in any place that needs
function returns no value and thus may not be used in any place that needs
a value. A void function does not produce any output when called by itself
on an input line. The key word \fBvoid\fR is placed between the key word
\fBdefine\fR and the function name. For example, consider the following
@ -520,27 +521,27 @@ no zero is printed because the function is a void function.
.PP
Also, call by variable for arrays was added. To declare
a call by variable array, the declaration of the array parameter in the
function definition looks like "\fI*name\fB[]\fR". The call to the
function remains the same as call by value arrays.
function definition looks like "\,\fI*name\/\fB[]\fR". The call to the
function remains the same as call by value arrays.
.SS MATH LIBRARY
If \fBbc\fR is invoked with the \fB-l\fR option, a math library is preloaded
and the default scale is set to 20. The math functions will calculate their
results to the scale set at the time of their call.
results to the scale set at the time of their call.
The math library defines the following functions:
.IP "s (\fIx\fR)"
.IP "s (\,\fIx\/\fR)"
The sine of x, x is in radians.
.IP "c (\fIx\fR)"
.IP "c (\,\fIx\/\fR)"
The cosine of x, x is in radians.
.IP "a (\fIx\fR)"
.IP "a (\,\fIx\/\fR)"
The arctangent of x, arctangent returns radians.
.IP "l (\fIx\fR)"
.IP "l (\,\fIx\/\fR)"
The natural logarithm of x.
.IP "e (\fIx\fR)"
.IP "e (\,\fIx\/\fR)"
The exponential function of raising e to the value x.
.IP "j (\fIn,x\fR)"
.IP "j (\,\fIn,x\/\fR)"
The Bessel function of integer order n of x.
.SS EXAMPLES
In /bin/sh, the following will assign the value of "pi" to the shell
In /bin/sh, the following will assign the value of "pi" to the shell
variable \fBpi\fR.
.RS
\f(CW
@ -567,7 +568,7 @@ define e(x) {
if (x<0) {
m = 1
x = \-x
}
}
/* Precondition x. */
z = scale;
@ -599,7 +600,7 @@ define e(x) {
.PP
The following is code that uses the extended features of \fBbc\fR to
implement a simple program for calculating checkbook balances. This
program is best kept in a file so that it can be used many times
program is best kept in a file so that it can be used many times
without having to retype it at every use.
.nf
.RS
@ -646,12 +647,12 @@ retained. For \fBreadline\fR, a value of \-1 means that an unlimited
number of history lines are retained. Setting the value of
\fBhistory\fR to a positive number restricts the number of history
lines to the number given. The value of 0 disables the history
feature. The default value is 100. For more information, read the
feature. The default value is 100. For more information, read the
user manuals for the GNU \fBreadline\fR, \fBhistory\fR and BSD \fBlibedit\fR
libraries. One can not enable both \fBreadline\fR and \fBlibedit\fR
at the same time.
.SS DIFFERENCES
This version of
This version of
.B bc
was implemented from the POSIX P1003.2/D11 draft and contains
several differences and extensions relative to the draft and
@ -666,7 +667,7 @@ debugging the parser and preparing the math library.
.PP
A major source of differences is
extensions, where a feature is extended to add more functionality and
additions, where new features are added.
additions, where new features are added.
The following is the list of differences and extensions.
.IP "LANG environment"
This version does not conform to the POSIX standard in the processing
@ -683,7 +684,7 @@ Strings are not allowed to contain NUL characters. POSIX says all characters
must be included in strings.
.IP "last"
POSIX \fBbc\fR does not have a \fBlast\fR variable. Some implementations
of \fBbc\fR use the period (.) in a similar way.
of \fBbc\fR use the period (.\&) in a similar way.
.IP "comparisons"
POSIX \fBbc\fR allows comparisons only in the if statement, the while
statement, and the second expression of the for statement. Also, only
@ -697,7 +698,7 @@ POSIX \fBbc\fR does not have the logical operators.
.IP "read function"
POSIX \fBbc\fR does not have a read function.
.IP "print statement"
POSIX \fBbc\fR does not have a print statement .
POSIX \fBbc\fR does not have a print statement.
.IP "continue statement"
POSIX \fBbc\fR does not have a continue statement.
.IP "return statement"
@ -709,7 +710,7 @@ not provide a method to specify an array as an actual parameter. (This
is most likely an oversight in the grammar.) Traditional implementations
of \fBbc\fR have only call by value array parameters.
.IP "function format"
POSIX \fBbc\fR requires the opening brace on the same line as the
POSIX \fBbc\fR requires the opening brace on the same line as the
\fBdefine\fR key word and the \fBauto\fR statement on the next line.
.IP "=+, =\-, =*, =/, =%, =^"
POSIX \fBbc\fR does not require these "old style" assignment operators to
@ -732,7 +733,7 @@ function will not be callable and becomes undefined.
Syntax errors in the interactive execution code will invalidate the
current execution block. The execution block is terminated by an
end of line that appears after a complete sequence of statements.
For example,
For example,
.nf
.RS
a = 1
@ -762,7 +763,7 @@ are removed during the
clean up process. During a non-interactive
session, the SIGINT signal will terminate the entire run of \fBbc\fR.
.SS LIMITS
The following are the limits currently in place for this
The following are the limits currently in place for this
.B bc
processor. Some of them may have been changed by an installation.
Use the limits statement to see the actual values.
@ -798,8 +799,8 @@ variables would typically contain function definitions for functions
the user wants defined every time \fBbc\fR is run.
.IP "BC_LINE_LENGTH"
This should be an integer specifying the number of characters in an
output line for numbers. This includes the backslash and newline characters
for long numbers. As an extension, the value of zero disables the
output line for numbers. This includes the backslash and newline characters
for long numbers. As an extension, the value of zero disables the
multi-line feature. Any other value of this variable that is less than
3 sets the line length to 70.
.SH DIAGNOSTICS
@ -814,7 +815,7 @@ Email bug reports to
Be sure to include the word ``bc'' somewhere in the ``Subject:'' field.
.SH AUTHOR
.nf
Philip A. Nelson
Philip A.\& Nelson
philnelson@acm.org
.fi
.SH ACKNOWLEDGEMENTS