Redirecting input streams
Unless you specify otherwise, many Unix commands take their input
from the keyboard. For example, the
cat command usually
takes input from the keyboard and sends it to the display screen:
yourname@yourcomputer<26>% cat Foo. Foo. Bar! Bar! ^DIn the above example, user input is shown in bold type. Note that every time you type a line, the line is typed back at you. Use the control-D character to terminate your input; this character is shown as
^Don your screen.
To redirect the input stream of a command means to execute it so
that the command reads its input from a given file.
To use input redirection, type a ``less-than'' character
<) at the end of the command,
and then type the name of the file you want to use for input.
yourname@yourcomputer<27>% cat <timestamp Sat Jan 28 15:03:08 MST 1995
John Shipman, email@example.com
Last updated: 1995/12/04 19:39:34 UT