CAT(1) System General Commands Manual

NAME

cat - concatenate and print files

SYNOPSIS

cat [-benstuv] [-] [file...]

DESCRIPTION

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 single spaced.

-t

Implies the -v option, and displays tab characters as ^I as well.

-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 (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 file2 > 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 utility appeared in Version 6 AT&T UNIX.

3rd Berkeley Distribution, May 2, 1995