1.\" Copyright (c) 1989, 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" the Institute of Electrical and Electronics Engineers, Inc. 6.\" 7.\" %sccs.include.redist.man% 8.\" 9.\" @(#)cat.1 8.1 (Berkeley) 06/29/93 10.\" 11.Dd 12.Dt CAT 1 13.Os BSD 3 14.Sh NAME 15.Nm cat 16.Nd concatenate and print files 17.Sh SYNOPSIS 18.Nm cat 19.Op Fl benstuv 20.Op Fl 21.Op Ar 22.Sh DESCRIPTION 23The 24.Nm cat 25utility reads files sequentially, writing them to the standard output. 26The 27.Ar file 28operands are processed in command line order. 29A single dash represents the standard input. 30.Pp 31The options are as follows: 32.Bl -tag -width Ds 33.It Fl b 34Implies the 35.Fl n 36option but doesn't number blank lines. 37.It Fl e 38Implies the 39.Fl v 40option, and displays a dollar sign 41.Pq Ql \&$ 42at the end of each line 43as well. 44.It Fl n 45Number the 46.Ar output 47lines, starting at 1. 48.It Fl s 49Squeeze multiple adjacent empty lines, causing the output to be 50single spaced. 51.It Fl t 52Implies the 53.Fl v 54option, and displays tab characters as 55.Pq Ql ^I 56as well. 57.It Fl u 58The 59.Fl u 60option guarantees that the output is unbuffered. 61.It Fl v 62Displays non-printing characters so they are visible. 63Control characters print as 64.Ql ^X 65for control-X; the delete 66character (octal 0177) prints as 67.Ql ^? 68Non-ascii characters (with the high bit set) are printed as 69.Ql M- 70(for meta) followed by the character for the low 7 bits. 71.El 72.Pp 73The 74.Nm cat 75utility exits 0 on success, and >0 if an error occurs. 76.Sh BUGS 77Because of the shell language mechanism used to perform output 78redirection, the command 79.Dq Li cat file1 file 2 > file1 80will cause the original data in file1 to be destroyed! 81.Sh SEE ALSO 82.Xr head 1 , 83.Xr more 1 , 84.Xr pr 1 , 85.Xr tail 1 86.Rs 87.%A Rob Pike 88.%T "UNIX Style, or cat -v Considered Harmful" 89.%J "USENIX Summer Conference Proceedings" 90.%D 1983 91.Re 92.Sh HISTORY 93A 94.Nm 95command appeared in Version 6 AT&T UNIX. 96