1.\" Copyright (c) 1989, 1990 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)cat.1 6.8 (Berkeley) 06/11/90 7.\" 8.Dd 9.Dt CAT 1 10.Os BSD 3 11.Sh NAME 12.Nm cat 13.Nd concatenate and print files 14.Sh SYNOPSIS 15.Nm cat 16.Op Fl benstuv 17.Op Fl 18.Ar 19.Sh DESCRIPTION 20The 21.Nm cat 22utility reads files sequentially, writing them to the standard output. 23The 24.Ar file 25operands are processed in command line order. 26A single dash represents standard input. 27.Pp 28The options are as follows: 29.Tp Fl b 30Implies the 31.Fl n 32option but doesn't number blank lines. 33.Tp Fl e 34Implies the 35.Fl v 36option, and displays a dollar sign (``$'') at the end of each line 37as well. 38.Tp Fl n 39Number the 40.Ar output 41lines, starting at 1. 42.Tp Fl s 43Squeeze multiple adjacent empty lines, causing the output to be 44single spaced. 45.Tp Fl t 46Implies the 47.Fl v 48option, and displays tab characters as ``^I'' as well. 49.Tp Fl u 50The 51.Fl u option guarantees that the output is unbuffered. 52.Tp Fl v 53Displays non-printing characters so they are visible. 54Control characters print line ``^X'' for control-X; the delete 55character (octal 0177) prints as ``^?''. 56Non-ascii characters (with the high bit set) are printed as 57`.`M-'' (for meta) followed by the character for the low 7 bits. 58.Tp 59.Pp 60.Nm cat 61is useful for getting files into a pipe, for instance, to sort 62two files together, 63the command 64.Pp 65.Dl cat file1 file2 | sort > sfile 66.Pp 67reads the contents of 68file1 and file2 sequentially, pipes it all to sort and places the 69newly sorted data in file3. 70.Pp 71Because of the shell language mechanism used to perform output 72redirection, the command ``cat file1 file 2 > file1'' will cause 73.P original data in file1 to be destroyed! 74.Pp 75.Nm Cat 76The cat utility exits 0 on success, and >0 if an error 77occurs. 78.Sh SEE ALSO 79.Xr head 1 , 80.Xr more 1 , 81.Xr pr 1 , 82.Xr tail 1 83.Pp 84Rob Pike, 85.Em UNIX Style, or cat -v Considered Harmful 86USENIX Summer Conference Proceedings, 1983. 87.Sh HISTORY 88The 89.Nm 90command appeared in Version 7 AT&T UNIX. 91