There are two distinct classes of input and output functions. The first set are modeled after the functions available in Matlab. The second set are modeled after the standard I/O library used by the C programming language and offer more flexibility and control over the output.
When running interactively, Octave normally sends any output intended
for your terminal that is more than one screen long to a paging program,
more. This avoids the problem of having a
large volume of output stream by before you can read it. With
less (and some versions of
more) you can also scan forward
and backward, and search for specific items.
Normally, no output is displayed by the pager until just before Octave
is ready to print the top level prompt, or read from the standard input
(for example, by using the
This means that there may be some delay before any output appears on
your screen if you have asked Octave to perform a significant amount of
work with a single command statement. The function
fflush may be
used to force output to be sent to the pager (or any other stream)
You can select the program to run as the pager by setting the variable
PAGER, and you can turn paging off by setting the value of the
page_screen_output to 0.
Turn output pagination on or off. Without an argument,
moretoggles the current state.
The default value is normally
"pg", depending on what programs are installed on your system. See Installation.
When running interactively, Octave sends any output intended for your terminal that is more than one screen long to the program named by the value of the variable
If the value of
page_screen_outputis nonzero, all output intended for the screen that is longer than one page is sent through a pager. This allows you to view one screenful at a time. Some pagers (such as
less—see Installation) are also capable of moving backward on the output. The default value is 1.
If the value of
page_output_immediatelyis nonzero, Octave sends output to the pager as soon as it is available. Otherwise, Octave buffers its output and waits until just before the prompt is printed to flush it to the pager. The default value is 0.
Flush output to fid. This is useful for ensuring that all pending output makes it to the screen before some other event occurs. For example, it is always a good idea to flush the standard output stream before calling
fflushreturns 0 on success and an OS dependent error value (−1 on unix) on error.