CAT(1) BSD Reference Manual CAT(1)
cat - concatenate and print files
cat [-benstuv] [-] [file ...]
The cat 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 -n option but doesn't number blank lines.
-e Implies the -v option, 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
-t Implies the -v option, and displays tab characters as `^I' as
-u The -u option 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 (oc-
tal 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.
Because of the shell language mechanism used to perform output redirec-
tion, the command ``cat file1 file 2 > file1'' will cause the original
data in file1 to be destroyed!
head(1), more(1), pr(1), tail(1), vis(1)
Rob Pike, "UNIX Style, or cat -v Considered Harmful", USENIX Summer
Conference Proceedings, 1983.
A cat command appeared in Version 6 AT&T UNIX.
3rd Berkeley Distribution May 2, 1995 1