plan9port/man/man1/cat.1

109 lines
1.6 KiB
Groff
Raw Normal View History

2004-04-10 18:53:55 +00:00
.TH CAT 1
.SH NAME
2005-01-03 06:40:20 +00:00
cat, read, nobs \- catenate files
2004-04-10 18:53:55 +00:00
.SH SYNOPSIS
.B cat
[
.I file ...
]
.br
.B read
[
.B -m
] [
.B -n
.I nline
] [
.I file ...
]
2005-01-03 06:40:20 +00:00
.br
nobs
[
.I file ...
]
2004-04-10 18:53:55 +00:00
.SH DESCRIPTION
.I Cat
reads each
.I file
in sequence and writes it on the standard output.
Thus
.IP
.L
cat file
.LP
prints a file and
.IP
.L
cat file1 file2 >file3
.LP
concatenates the first two files and places the result
on the third.
.PP
If no
.I file
is given,
.I cat
reads from the standard input.
Output is buffered in blocks matching the input.
.PP
.I Read
copies to standard output exactly one line from the named
.IR file ,
default standard input.
It is useful in interactive
.IR rc (1)
scripts.
.PP
The
.B -m
flag causes it to continue reading and writing multiple lines until end of file;
.B -n
causes it to read no more than
.I nline
lines.
.PP
2005-01-03 06:40:20 +00:00
.I Read
always executes a single
2004-04-10 18:53:55 +00:00
.B write
for each line of input, which can be helpful when
preparing input to programs that expect line-at-a-time data.
It never reads any more data from the input than it prints to the output.
2005-01-03 06:40:20 +00:00
.PP
.I Nobs
copies the named files to
standard output except that it removes all backspace
characters and the characters that precede them.
It is useful to use as
.B $PAGER
with the Unix version of
.IR man (1)
when run inside a
.I win
(see
.IR acme (1))
window.
2004-04-10 18:53:55 +00:00
.SH SOURCE
2004-04-19 19:22:56 +00:00
.B /usr/local/plan9/src/cmd/cat.c
2004-04-10 18:53:55 +00:00
.br
2004-04-19 19:22:56 +00:00
.B /usr/local/plan9/src/cmd/read.c
2005-01-03 06:40:20 +00:00
.br
.B /usr/local/plan9/bin/nobs
2004-04-10 18:53:55 +00:00
.SH SEE ALSO
.IR cp (1)
.SH DIAGNOSTICS
.I Read
exits with status
.B eof
on end of file or, in the
.B -n
case, if it doesn't read
.I nlines
lines.
.SH BUGS
Beware of
.L "cat a b >a"
and
.LR "cat a b >b" ,
which
destroy input files before reading them.