CAT(1)                    BSD General Commands Manual                   CAT(1)

NAME
     cat -- concatenate and print files

SYNOPSIS
     cat [-benstuv] [file ...]

DESCRIPTION
     The 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, cat reads from the standard input.  If
     file is a UNIX domain socket, cat connects to it and then reads it until
     EOF.  This complements the UNIX domain binding capability available in
     inetd(8).

     The options are as follows:

     -b      Number the non-blank output lines, starting at 1.

     -e      Display non-printing characters (see the -v option), and display
             a dollar sign (`$') at the end of each line.

     -n      Number the output lines, starting at 1.

     -s      Squeeze multiple adjacent empty lines, causing the output to be
             single spaced.

     -t      Display non-printing characters (see the -v option), and display
             tab characters as `^I'.

     -u      Disable output buffering.

     -v      Display non-printing characters so they are visible.  Control
             characters print as `^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.

EXIT STATUS
     The cat utility exits 0 on success, and >0 if an error occurs.

EXAMPLES
     The command:

           cat file1

     will print the contents of file1 to the standard output.

     The command:

           cat file1 file2 > file3

     will 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 (i.e., sh(1)) for more information on redirection.

     The command:

           cat file1 - file2 - file3

     will print the contents of file1, print data it receives from the stan-
     dard 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 `-' operand.

SEE ALSO
     head(1), more(1), pr(1), sh(1), tail(1), vis(1), zcat(1), setbuf(3)

     Rob Pike, "UNIX Style, or cat -v Considered Harmful", USENIX Summer
     Conference Proceedings, 1983.

STANDARDS
     The cat utility is compliant with the IEEE Std 1003.2-1992 (``POSIX.2'')
     specification.

     The flags [-benstv] are extensions to the specification.

HISTORY
     A cat utility appeared in Version 1 AT&T UNIX.  Dennis Ritchie designed
     and wrote the first man page.  It appears to have been cat(1).

BUGS
     Because of the shell language mechanism used to perform output redirect-
     ion, the command ``cat file1 file2 > file1'' will cause the original data
     in file1 to be destroyed!

     The cat utility does not recognize multibyte characters when the -t or -v
     option is in effect.

BSD                             March 21, 2004                             BSD