NAME

cat − concatenate and display

SYNOPSIS

cat [ − ] [ −benstuv ] [ filename... ]

SYSTEM V SYNOPSIS

/usr/5bin/cat [ − ] [ −estuv ] [ filename... ]

AVAILABILITY

The System V version of this command is available with the System V software installation option.  Refer to Installing SunOS 4.1 for information on how to install optional software. 

DESCRIPTION

cat reads each filename in sequence and displays it on the standard output.  Thus:

example% cat goodies

displays the contents of goodies on the standard output, and

example% cat goodies1 goodies2 > goodies3

concatenates the first two files and places the result on the third. 

If no filename argument is given, or if the argument ‘−’ is given, cat reads from the standard input.  If the standard input is a terminal, input is terminated by an EOF condition. 

OPTIONS

−b Number the lines, as −n, but omit the line numbers from blank lines. 

−e Display non-printing characters, as −v, and in addition display a $ character at the end of each line. 

−n Precede each line output with its line number. 

−s Substitute a single blank line for multiple adjacent blank lines. 

−t Display non-printing characters, as −v, and in addition display TAB characters as ^I (CTRL-I). 

−u Unbuffered.  If −u is not used, output is buffered in blocks, or line-buffered if standard output is a terminal. 

−v Display non-printing characters (with the exception of TAB and NEWLINE characters) so that they are visible.  Control characters print like ^X for CTRL-X; the DEL character (octal 0177) print as ‘^?’.  Non-ASCII characters (with the high bit set) are displayed as M−x where M− stands for ‘meta’ and x is the character specified by the seven low order bits. 

SYSTEM V OPTIONS

−e If the −v option is specified, display a $ character at the end of each line. 

−s Suppress messages about files which cannot be opened. 

−t If the −v option is specified, display TAB characters as ^I (CTRL-I) and FORMFEED characters as ^L (CTRL-L). 

−v Display non-printing character (with the exception of TAB, NEWLINE, and FORMFEED characters) so that they are visible. 

ENVIRONMENT

The environment variables LC_CTYPE, LANG, and LC_default control the character classification throughout cat.  On entry to cat, these environment variables are checked in the following order: LC_CTYPE, LANG, and LC_default.  When a valid value is found, remaining environment variables for character classification are ignored.  For example, a new setting for LANG does not override the current valid character classification rules of LC_CTYPE.  When none of the values is valid, the shell character classification defaults to the POSIX.1 “C” locale. 

SEE ALSO

cp(1), ex(1), more(1), pg(1V), pr(1V), tail(1)

NOTES

Beware of ‘cat a b > a’ and ‘cat a b > b’, which destroy the input files before reading them. 

Sun Release 4.1  —  Last change: 19 July 1989