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CAT(1)			     General Commands Manual			  CAT(1)

NAME
     cat -- concatenate and print files

SYNOPSIS
     cat [-AbeElnstTuv] [file ...]

DESCRIPTION
     The cat utility reads files sequentially, writing them to the standard out-
     put.   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:

     -A      Equivalent to specifying the -v , -E and -T options.

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

     -e      Equivalent to specifying the -E and -v options.

     -E      Display a dollar sign (`$') at the end of each line.

     -l      Set an exclusive advisory lock on the standard output file descrip-
	     tor.  This lock is set using fcntl(2) with  the  F_SETLKW	command.
	     If the output file is already locked, cat will block until the lock
	     is acquired.

     -n      Number the output lines, starting at 1.

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

     -T      Display tab characters as `^I'.

     -t      Equivalent to specifying the -T and -v options.

     -u      Disable output buffering.

     -v      Display non-printing characters so they are visible.  Control char-
	     acters 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
     (e.g., 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	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 refers 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), fcntl(2), set-
     buf(3)

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

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

     The flags [-AbeElnstTv] 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 for cat.

BUGS
     Because of the shell language mechanism used to perform output redirection,
     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.

FreeBSD 16.0 CURRENT		 August 21, 2026			  CAT(1)
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