CAT(1)
NAME
cat − catenate and print
USAGE
cat [ −u ] [−n [b] ] [ −s ] [−v[et] file ...
DESCRIPTION
Cat reads each file in sequence and displays it on the standard output. Thus,
cat file
displays the file on the standard output, and
cat file1 file2 >file3
concatenates the first two files and places the result on the third.
If you fail to specify an input file, or if you use a dash (−) in place of a filename, cat reads from the standard input file. Output is buffered in 1024-byte blocks unless the standard output is a terminal, in which case it is line-buffered.
OPTIONS
−u Make output completely unbuffered.
−n Display output lines preceded by lines numbers, numbered sequentially from 1. When a b is also specified, omit line numbers from blank lines.
−s Crush out multiple adjacent empty lines so that the output appears single-spaced.
−v[et] Make non-printing characters visible. Control characters print like ^Z for CONTROL-Z; 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 of the low 7 bits. With an e keyletter also specified, display a dollar sign ($) character at the end of each line. With the t keyletter specified, display tab characters as ^I.
CAUTIONS
Beware of “cat a b >a” and “cat a b >b”, which destroy the input files before reading them.