NAME
cat —
concatenate and print files
SYNOPSIS
cat |
[-benstuv] [-]
[file ...] |
DESCRIPTION
Thecat utility reads files sequentially, writing them
to the standard output. The file operands are processed
in command line order. A single dash represents the standard input.
The options are as follows:
-b- Implies the
-noption but doesn't number blank lines. -e- Implies the
-voption, and displays a dollar sign (‘$’) at the end of each line as well. -n- Number the output lines, starting at 1.
-s- Squeeze multiple adjacent empty lines, causing the output to be single spaced.
-t- Implies the
-voption, and displays tab characters as ‘^I’ as well. -u- The
-uoption guarantees that the output is unbuffered. -v- Displays non-printing characters so they are visible. Control characters
print as ‘
^X’ for control-X; the delete character (octal 0177) prints as ‘^?’ Non-ascii characters (with the high bit set) are printed as ‘M-’ (for meta) followed by the character for the low 7 bits.
The cat utility exits 0 on success, and
>0 if an error occurs.
BUGS
Because of the shell language mechanism used to perform output
redirection, the command “cat file1 file 2 >
file1” will cause the original data in file1 to be
destroyed!
SEE ALSO
head(1), more(1), pr(1), tail(1), vis(1)
Rob Pike, “UNIX Style, or cat -v Considered Harmful”, USENIX Summer Conference Proceedings, 1983.
HISTORY
A cat command appeared in Version 6
AT&T UNIX.