CAT(1)CAT(1)
NAME
cat, read – catenate files
SYNOPSIS
cat
[
file ...
]
read
[
-m
] [
-n
nlines
] [
-c
nbytes
] [
file ...
]
DESCRIPTION
Cat
reads each
file
in sequence and writes it on the standard output.
Thus
cat file
prints a file and
cat file1 file2 >file3
concatenates the first two files and places the result
on the third.
If no
file
is given,
cat
reads from the standard input.
Output is buffered in blocks matching the input.
Read
copies to standard output exactly one line from the named
file,
default standard input.
It is useful in interactive
rc(1)
scripts.
The
-m
flag causes it to continue reading and writing multiple lines until end of file;
-n
causes it to read no more than
nlines
lines.
With the
-c
flag,
read
copies exactly
nbytes
of characters instead of lines. It is mutually exclusive with
-n
and
-m
flag.
Read
always executes a single
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.
SOURCE
/sys/src/cmd/cat.c
/sys/src/cmd/read.c
SEE
cp(1)
DIAGNOSTICS
Read
exits with status
eof
on end of file or, in the
-n
case, if it doesn’t read
nlines
lines.
BUGS
Beware of
cat a b >a
and
cat a b >b ,
which
destroy input files before reading them.