CAT(1) | General Commands Manual | CAT(1) |
cat | [-beflnstuv] [-] [file ...] |
The word “concatenate” is just a verbose synonym for “catenate”.
The options are as follows:
$
') at the end of each line as well.^I
' as well.^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.
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 (i.e., 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 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.
Rob Pike, UNIX Style, or cat -v Considered Harmful, USENIX Summer Conference Proceedings, 1983.
The flags [-belnstv] are extensions to the specification.
cat file1 file2 > file1
” will cause the original data in file1 to be destroyed! This is performed by the shell before cat is run.September 23, 2006 | NetBSD 6.1 |