help quietly, help noisily
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Title
[P] quietly -- Quietly and noisily perform Stata command
Syntax
Perform command but suppress terminal output
quietly [:] command
Perform command and ensure terminal output
noisily [:] command
Specify type of output to display
set output { proc | inform | error }
Description
quietly suppresses all terminal output for the duration of command. It
is useful both interactively and in programs.
noisily turns back on terminal output, if appropriate, for the duration
of command. It is useful only in programs.
set output specifies the output to be displayed. It is useful only in
programs and even then is seldom used.
Example of interactive use
You do not care to see the output from a particular regression, but
instead want to silently run the regression so that you may access some
of its returned results.
. sysuse auto
. quietly regress mpg weight foreign headroom
No output is presented, but the e() returned results from the regression
are now available.
Note for programmers
If you write a program or ado-file, say, mycmd, there is nothing special
you need to do so that your command can be prefixed with quietly. That
said, c-class value c(noisily) (see [P] creturn) will return 0 if output
is being suppressed and 1 otherwise. Thus your program might read
program mycmd
...
display ...
display ...
...
end
or
program mycmd
...
if c(noisily) {
display ...
display ...
}
...
end
The first style is preferred. If the user executes quietly mycmd, the
output from display itself, along with the output of all other commands,
will be automatically suppressed.
If the program must work substantially to produce what is being
displayed, however, and the only reason for doing that work is because of
the display, then the second style is preferred. In such cases, you can
include the extra work within the block of code executed only when
c(noisily) is true and thus make your program execute more quickly when
it is invoked quietly.
Also see
Manual: [P] quietly
Help: [P] capture
