File: coreutils.info,  Node: cat invocation,  Next: tac invocation,  Up: Output of entire files

3.1 ‘cat’: Concatenate and write files
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‘cat’ copies each FILE (‘-’ means standard input), or standard input if
none are given, to standard output.  Synopsis:

     cat [OPTION] [FILE]...

   The program accepts the following options.  Also see *note Common
options::.

‘-A’
‘--show-all’
     Equivalent to ‘-vET’.

‘-b’
‘--number-nonblank’
     Number all nonempty output lines, starting with 1.

‘-e’
     Equivalent to ‘-vE’.

‘-E’
‘--show-ends’
     Display a ‘$’ after the end of each line.  The ‘\r\n’ combination
     is shown as ‘^M$’.

‘-n’
‘--number’
     Number all output lines, starting with 1.  This option is ignored
     if ‘-b’ is in effect.

‘-s’
‘--squeeze-blank’
     Suppress repeated adjacent blank lines; output just one empty line
     instead of several.

‘-t’
     Equivalent to ‘-vT’.

‘-T’
‘--show-tabs’
     Display TAB characters as ‘^I’.

‘-u’
     Ignored; for POSIX compatibility.

‘-v’
‘--show-nonprinting’
     Display control characters except for LFD and TAB using ‘^’
     notation and precede characters that have the high bit set with
     ‘M-’.

   On systems like MS-DOS that distinguish between text and binary
files, ‘cat’ normally reads and writes in binary mode.  However, ‘cat’
reads in text mode if one of the options ‘-bensAE’ is used or if ‘cat’
is reading from standard input and standard input is a terminal.
Similarly, ‘cat’ writes in text mode if one of the options ‘-bensAE’ is
used or if standard output is a terminal.

   An exit status of zero indicates success, and a nonzero value
indicates failure.

   Examples:

     # Output f's contents, then standard input, then g's contents.
     cat f - g

     # Copy standard input to standard output.
     cat