Commodore PC 10 - Filters and Pipes; Command Pipes

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Often, it's useful to have input for a command come from a file
instead
of from the keyboard. This is possible in MS-DOS by using
a less-than sign (
<) in your command. For example, the following
command sorts the file names and sends the sorted output to a
file called
namelist:
sort < names> namelist
Filters and Pipes
A filter is a command that reads your input, transforms it in some
way, and then outputs it to your screen. In this manner the input
is "filtered" by the program. '
MS· DOS filters include: find, more, and sort. Their functions are
as follows:
flnd
more
sort
Searches for text in a file.
Displays
the contents of a file one screenful at
a time.
Alphabetically sorts
the contents of a file.
You
can redirect the output from a filter into a file, or use it as
input for another filter by using pipes. The following section
explains
how filters are piped together.
Command Pipes
If you want to use the output from one command as the input for
another,
you can pipe the commands to MS-DOS. Piping is done by
separating commands with the pipe symbol, which is a vertical
bar ( I ). The following command, for example, displays an alpha-
betically
sorted listing of your directory on the screen:
dir : sort
The pipe sends all output generated by the dir command (on the
left side of the bar) as input to the sort command (on the right
side
of the bar).
You
can also use piping with redirection if you want to send the
output to a file. For example, the following command creates a
file
named direct 1st on your default drive:
dir : sort> direct.lst
About Commands 17
MS-DOS filter
commands
Piping commands