Howto: UNIX or Linux convert DOS newlines CR-LF to Unix/Linux format
Q. How do I convert DOS newlines CR/LF to Unix/Linux format?
A. To converts text files between DOS and Unix formats you need to use special utility called dos2unix.
DOS text files traditionally have carriage return and line feed pairs as their newline characters while Unix text files have the line feed as their newline character.
UNIX/Linux Commands
- dos2unix (also known as fromdos) - converts text files from the DOS format to the Unix
format - unix2dos (also known as todos) - converts text files from the Unix format to the DOS format.
- sed - You can use sed command for same purpose
Task: Convert DOS file to UNIX format
Type the following command to convert file called myfile.txt:
$ dos2unix myfile.txt
However above command will not make a backup of original file myfile.txt. To make a backup of original file. The original file is renamed with the original filename and a .bak extension. Type the following command:
$ dos2unix -b myfile.txt
Task: Convert UNIX file to DOS format
Type the following command to convert file called myfile.txt:
$ unix2dos myfile.txt
$ unix2dos -b myfile.txt
Task: Convert DOS newlines (CR/LF) to Unix format using sed command
If you are using BASH shell type the following command (press Ctrl-V then Ctrl-M to get pattern or special symbol)
$ sed 's/^M$//' input.txt > output.txt
Task: Convert UNIX to DOS format using sed command
Type the following command if you are using bash shell:
$ sed 's/$'"/`echo \\\r`/" input.txt > output.txt
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January 4th, 2007 at 2:10 am
Howto: UNIX or Linux convert DOS newlines CR-LF to Unix/Linux format
THANK YOU! to who ever wrote this. I’ve been messing around with this for quite a while. This even works on AIX’s legacy version of sed. My day has been so made by this little nugget.
February 2nd, 2007 at 1:42 pm
I had tried the suggestion from Wikipedia and that did not work. This solution worked perfectly first time. THANK YOU.
September 5th, 2007 at 2:44 pm
Your UNIX to DOS sed script is incorrect if what you want is CRLF.
$ echo | sed ’s/$’”/`echo \\\r`/” | hexdump
0000000 0a0d
ASCII 0/13 is decimal 013, hex 0d, octal 015, bits 00001101: called ^M, CR
Official name: Carriage Return
ASCII 0/10 is decimal 010, hex 0a, octal 012, bits 00001010: called ^J, LF, NL
Official name: Line Feed
For CRLF you want 0d0a. Your producing LFCR here.
December 12th, 2007 at 6:23 am
Dear John,
Actually, the scripts are correct. Hexdump is reversing the byte order (integer format)
Try this for example and as a simplified script:
$ echo TEST | sed ’s/$/\r/’ | hexdump -C
Then try it without the -C.
You will notice that the 54’s (T) are next to each other. (ETTS)