[unix-history] / usr / src / bin / cat / cat.1

.\" Copyright (c) 1989, 1990 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)cat.1	6.14 (Berkeley) %G%
.\"
.Dd 
.Dt CAT 1
.Os BSD 3
.Sh NAME
.Nm cat
.Nd concatenate and print files
.Sh SYNOPSIS
.Nm cat
.Op Fl benstuv
.Op Fl
.Ar
.Sh DESCRIPTION
The
.Nm cat
utility reads files sequentially, writing them to the standard output.
The
.Ar file
operands are processed in command line order.
A single dash represents standard input.
.Pp
The options are as follows:
.Tw Ds
.Tp Fl b
Implies the
.Fl n
option but doesn't number blank lines.
.Tp Fl e
Implies the
.Fl v
option, and displays a dollar sign (``$'') at the end of each line
as well.
.Tp Fl n
Number the
.Ar output
lines, starting at 1.
.Tp Fl s
Squeeze multiple adjacent empty lines, causing the output to be
single spaced.
.Tp Fl t
Implies the
.Fl v
option, and displays tab characters as ``^I'' as well.
.Tp Fl u
The
.Fl u
option guarantees that the output is unbuffered.
.Tp Fl v
Displays non-printing characters so they are visible.
Control characters print line ``^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.
.Tp
.Pp
.Nm Cat
is useful for getting files into a pipe, for instance, to sort
two files together,
the command
.Pp
.Dl cat file1 file2 | sort > sfile
.Pp
reads the contents of
file1 and file2 sequentially, pipes it all to sort and places the
newly sorted data in file3.
.Pp
Because of the shell language mechanism used to perform output
redirection, the command ``cat file1 file 2 > file1'' will cause
.P original data in file1 to be destroyed!
.Pp
The
.Nm cat
utility exits 0 on success, and >0 if an error
occurs.
.Sh SEE ALSO
.Xr head 1 ,
.Xr more 1 ,
.Xr pr 1 ,
.Xr tail 1
.Pp
Rob Pike,
.Em UNIX Style, or cat -v Considered Harmful
USENIX Summer Conference Proceedings, 1983.
.Sh HISTORY
The
.Nm
command appeared in Version 7 AT&T UNIX.
Commit	Line	Data
b5dc1377	1	.\" Copyright (c) 1989, 1990 The Regents of the University of California.
ea642694	2	.\" All rights reserved.
e8cca28c	3	.\"
27c71911	4	.\" %sccs.include.redist.man%
ea642694	5	.\"
0e853b88	6	.\" @(#)cat.1 6.14 (Berkeley) %G%
e8cca28c	7	.\"
b5dc1377 CL	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
ea642694	20	The
b5dc1377	21	.Nm cat
ea642694	22	utility reads files sequentially, writing them to the standard output.
334f3902	23	The
b5dc1377	24	.Ar file
ea642694 KB	25	operands are processed in command line order.
ea642694 KB	26	A single dash represents standard input.
b5dc1377	27	.Pp
49c5b53c	28	The options are as follows:
5325ced3	29	.Tw Ds
b5dc1377	30	.Tp Fl b
49c5b53c	31	Implies the
b5dc1377	32	.Fl n
49c5b53c	33	option but doesn't number blank lines.
b5dc1377	34	.Tp Fl e
49c5b53c	35	Implies the
b5dc1377	36	.Fl v
49c5b53c KB	37	option, and displays a dollar sign (``$'') at the end of each line
49c5b53c KB	38	as well.
b5dc1377	39	.Tp Fl n
49c5b53c	40	Number the
b5dc1377	41	.Ar output
49c5b53c	42	lines, starting at 1.
b5dc1377	43	.Tp Fl s
49c5b53c KB	44	Squeeze multiple adjacent empty lines, causing the output to be
49c5b53c KB	45	single spaced.
b5dc1377	46	.Tp Fl t
49c5b53c	47	Implies the
b5dc1377	48	.Fl v
49c5b53c	49	option, and displays tab characters as ``^I'' as well.
b5dc1377	50	.Tp Fl u
334f3902	51	The
5325ced3 CL	52	.Fl u
5325ced3 CL	53	option guarantees that the output is unbuffered.
b5dc1377	54	.Tp Fl v
49c5b53c KB	55	Displays non-printing characters so they are visible.
	56	Control characters print line ``^X'' for control-X; the delete
	57	character (octal 0177) prints as ``^?''.
	58	Non-ascii characters (with the high bit set) are printed as
b5dc1377 CL	59	`.`M-'' (for meta) followed by the character for the low 7 bits.
	60	.Tp
	61	.Pp
5325ced3	62	.Nm Cat
b5dc1377 CL	63	is useful for getting files into a pipe, for instance, to sort
	64	two files together,
	65	the command
	66	.Pp
	67	.Dl cat file1 file2 \| sort > sfile
	68	.Pp
	69	reads the contents of
	70	file1 and file2 sequentially, pipes it all to sort and places the
	71	newly sorted data in file3.
	72	.Pp
ea642694 KB	73	Because of the shell language mechanism used to perform output
ea642694 KB	74	redirection, the command ``cat file1 file 2 > file1'' will cause
5325ced3	75	.P original data in file1 to be destroyed!
b5dc1377	76	.Pp
e88f810f KB	77	The
	78	.Nm cat
	79	utility exits 0 on success, and >0 if an error
b5dc1377 CL	80	occurs.
	81	.Sh SEE ALSO
	82	.Xr head 1 ,
	83	.Xr more 1 ,
	84	.Xr pr 1 ,
	85	.Xr tail 1
	86	.Pp
	87	Rob Pike,
	88	.Em UNIX Style, or cat -v Considered Harmful
ea642694	89	USENIX Summer Conference Proceedings, 1983.
b5dc1377 CL	90	.Sh HISTORY
	91	The
	92	.Nm
	93	command appeared in Version 7 AT&T UNIX.