|CAT(1)||General Commands Manual||CAT(1)|
cat — concatenate
and print files
cat utility reads files sequentially,
writing them to the standard output. The file operands
are processed in command-line order. If file is a
single dash (‘-’) or absent,
from the standard input.
The options are as follows:
-noption but doesn't count blank lines.
-voption and also prints a dollar sign (‘
$’) at the end of each line.
-voption and also prints tab characters as ‘
^X’ for control-X, with the exception of the tab and EOL characters, which are displayed normally. The tab character, control-I, can be made visible via the
-toption. The DEL 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.
cat utility exits 0 on success,
and >0 if an error occurs.
Print the contents of file1 to the standard output:
$ cat file1
Sequentially print the contents of file1 and file2 to the file file3, truncating file3 if it already exists. See the manual page for your shell (e.g., sh(1)) for more information on redirection.
$ cat file1 file2 > file3
Print the contents of file1, print data it
receives from the standard input until it receives an
EOF (‘^D’) character, print the
contents of file2, read and output contents of the
standard input again, then finally output the contents of
file3. Note that if the standard input referred to a
file, the second dash on the command-line would have no effect, since the
entire contents of the file would have already been read and printed by
cat when it encountered the first
$ cat file1 - file2 - file3
Rob Pike, UNIX Style, or cat -v Considered Harmful, USENIX Summer Conference Proceedings, 1983.
cat utility is compliant with the
IEEE Std 1003.1-2008 (“POSIX.1”)
The flags [
-benstv] are extensions to that
cat utility appeared in
Version 1 AT&T UNIX.
Because of the shell language mechanism used to perform output redirection, the following command will cause the original data in file1 to be destroyed:
$ cat file1 file2 > file1
To append file2 to file1, instead use:
$ cat file2 >> file1
|March 5, 2011||OpenBSD-5.1|