NAME    [Toc]    [Back]

     cat - concatenate and print files

SYNOPSIS    [Toc]    [Back]

     cat [-benstuv] [file ...]

DESCRIPTION    [Toc]    [Back]

     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.

     The options are as follows:

     -b      Implies the -n option but doesn't count blank lines.

     -e      Implies the -v option and also prints 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      Implies the -v option and also prints tab characters
as `^I'.

     -u       The output is guaranteed to be unbuffered (see setbuf(3)).

     -v      Displays non-printing characters so they  are  visible.  Control
             characters print 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 -t
option.  The
             DEL character (octal 0177)  prints  as  `^?'.   NonASCII characters
             (with  the  high  bit  set) are printed as `M-' (for
meta) followed
             by the character for the low 7 bits.

     The cat utility exits 0 on success or >0  if  an  error  occurred.

EXAMPLES    [Toc]    [Back]

     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 `-' operand.

           $ cat file1 - file2 - file3

SEE ALSO    [Toc]    [Back]

     head(1),  less(1),  more(1),  pr(1), sh(1), tail(1), vis(1),
setbuf(3)

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

STANDARDS    [Toc]    [Back]

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

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

HISTORY    [Toc]    [Back]

     A cat utility appeared in Version 1 AT&T UNIX.

BUGS    [Toc]    [Back]

     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!

OpenBSD      3.6                            May      2,      1995