FreeBSD General Commands Manual


Cat - concatenate and print files


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


The cat utility reads files sequentially, writing them to the standard output. The file operands are processed in command line order. A single dash represents the standard input.

The options are as follows:

    -b Number the non-blank output lines, starting at 1.
    -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 The -u option guarantees that the output is unbuffered.
    -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.


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


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!


head(1), more(1), pr(1), tail(1), vis(1)

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


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

3rd Berkeley Distribution May 2, 1995