cat(1)
Name
cat − concatenate and print data
Syntax
cat [ −b ] [ −e ] [ −n ] [ −s ] [ −t ] [ −u ] [ −v ] file...
Description
The cat command reads each file in sequence and displays it on the standard output. Therefore, to display the file on the standard output you type:
cat file
To concatenate two files and place the result on the third you type:
cat file1 file2 > file3
To concatenate two files and append them to a third you type:
cat file1 file2 >> file3
If no input file is given, or if a minus sign (−) is encountered as an argument, cat reads from the standard input file. Output is buffered in 1024-byte blocks unless the standard output is a terminal, in which case it is line buffered. The cat utility supports the processing of 8-bit characters.
Options
−b Ignores blank lines and precedes each output line with its line number.
−e Displays a dollar sign ($) at the end of each output line.
−n Precedes all output lines (including blank lines) with line numbers.
−s Squeezes adjacent blank lines from output and single spaces output.
−t Displays non-printing characters (including tabs) in output. In addition to those representations used with the −v option, all tab characters are displayed as ^I.
−u Unbuffers output.
−v Displays non-printing characters (excluding tabs and newline) as the ^x. If the character is in the range octal 0177 to octal 0241, it is displayed as M-x. The delete character (octal 0177) displays as ^?. For example, <CTRLX> is displayed as ^X.
Restriction
Do not redirect output to one of the input files using the > (redirection symbol). If you do this, you lose the original data in the input file because the shell truncates it before cat can read it.