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.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. All advertising materials mentioning features or use of this software 16.\" must display the following acknowledgement: 17.\" This product includes software developed by the University of 18.\" California, Berkeley and its contributors. 19.\" 4. Neither the name of the University nor the names of its contributors 20.\" may be used to endorse or promote products derived from this software 21.\" without specific prior written permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33.\" SUCH DAMAGE. 34.\" 35.\" @(#)cat.1 8.3 (Berkeley) 5/2/95 36.\" $FreeBSD$ 37.\" 38.Dd May 2, 1995 39.Dt CAT 1 40.Os 41.Sh NAME 42.Nm cat 43.Nd concatenate and print files 44.Sh SYNOPSIS 45.Nm 46.Op Fl benstuv 47.Op Ar 48.Sh DESCRIPTION 49The 50.Nm 51utility reads files sequentially, writing them to the standard output. 52The 53.Ar file 54operands are processed in command-line order. 55If 56.Ar file 57is a single dash 58.Pq Sq \&- 59or absent, 60.Nm 61reads from the standard input. 62.Pp 63The options are as follows: 64.Bl -tag -width indent 65.It Fl b 66Number the non-blank output lines, starting at 1. 67.It Fl e 68Display non-printing characters (see the 69.Fl v 70option), and display a dollar sign 71.Pq Ql \&$ 72at the end of each line. 73.It Fl n 74Number the output lines, starting at 1. 75.It Fl s 76Squeeze multiple adjacent empty lines, causing the output to be 77single spaced. 78.It Fl t 79Display non-printing characters (see the 80.Fl v 81option), and display tab characters as 82.Ql ^I . 83.It Fl u 84The 85.Fl u 86option guarantees that the output is unbuffered. 87.It Fl v 88Display non-printing characters so they are visible. 89Control characters print as 90.Ql ^X 91for control-X; the delete 92character (octal 0177) prints as 93.Ql ^? . 94.Pf Non- Tn ASCII 95characters (with the high bit set) are printed as 96.Ql M- 97(for meta) followed by the character for the low 7 bits. 98.El 99.Sh DIAGNOSTICS 100The 101.Nm 102utility exits 0 on success or >0 if an error occurred. 103.Sh EXAMPLES 104The command: 105.Bd -literal -offset indent 106.Ic cat file1 107.Ed 108.Pp 109will print the contents of 110.Ar file1 111to the standard output. 112.Pp 113The command: 114.Bd -literal -offset indent 115.Ic cat file1 file2 > file3 116.Ed 117.Pp 118will sequentially print the contents of 119.Ar file1 120and 121.Ar file2 122to the file 123.Ar file3 , 124truncating 125.Ar file3 126if it already exists. 127See the manual page for your shell (i.e., 128.Xr sh 1 ) 129for more information on redirection. 130.Pp 131The command: 132.Bd -literal -offset indent 133.Ic cat file1 - file2 - file3 134.Ed 135.Pp 136will print the contents of 137.Ar file1 , 138print data it receives from the standard input until it receives an 139.Dv EOF 140.Pq Sq ^D 141character, print the contents of 142.Ar file2 , 143read and output contents of the standard input again, then finally output 144the contents of 145.Ar file3 . 146Note that if the standard input referred to a file, the second dash 147on the command-line would have no effect, since the entire contents of the file 148would have already been read and printed by 149.Nm 150when it encountered the first 151.Ql \&- 152operand. 153.Sh SEE ALSO 154.Xr head 1 , 155.Xr more 1 , 156.Xr pr 1 , 157.Xr sh 1 , 158.Xr tail 1 , 159.Xr vis 1 , 160.Xr zcat 1 , 161.Xr setbuf 3 162.Rs 163.%A Rob Pike 164.%T "UNIX Style, or cat -v Considered Harmful" 165.%J "USENIX Summer Conference Proceedings" 166.%D 1983 167.Re 168.Sh STANDARDS 169The 170.Nm 171utility is compliant with the 172.St -p1003.2-92 173specification. 174.Pp 175The flags 176.Op Fl benstv 177are extensions to the specification. 178.Sh HISTORY 179A 180.Nm 181utility appeared in 182.At v1 . 183.An Dennis Ritchie 184designed and wrote the first man page. 185It appears to have been 186.Xr cat 1 . 187.Sh BUGS 188Because of the shell language mechanism used to perform output 189redirection, the command 190.Dq Li cat file1 file2 > file1 191will cause the original data in file1 to be destroyed! 192