MPE/iX Shell and Utilities Reference Manual, Vol 1

bc(1) MPE/iX Shell and Utilities bc(1)

quit

terminates bc. In other implementations of bc, the interpreter exits as soon as it reads

this token. This version of bc treats quit as a real statement, so you can use it in loops,

functions, and so on.

sh ...

lets you send a line to the

MPE/iX Shell for execution, as in

sh more <foo

This command passes everything from the ﬁrst non-blank character until the end of the

line to the shell for execution.

void expression

void throws away or voids the result of the evaluation of expression instead of display-

ing it. This is useful when using ++ and -- operators, or when you want to use a func-

tion but don’t want to use the return value for anything. For example,

void foo++

increments foo but does not display the result. The void statement is unique to this

version of bc.

Several other types of statements are only relevant in function deﬁnitions. These are

described in the next section.

Functions

A function is a subprogram to calculate a result based on argument values. For example, the

following function converts a temperature given in Fahrenheit into the equivalent temperature

in Celsius.

define f_to_c(f) {

return ((f-32)*5/9)

}

This deﬁnes a function named f_to_c() that takes a single argument called f. The body of

the function is enclosed in brace brackets. The opening brace must be on the same line as the

define keyword. The function body consists of a sequence of statements to calculate the

result of the function. An expression of the form

return (expression)

returns the value of expression as the result of the function. The parentheses around the

expression are optional.

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