Removing Control Characters from a File

I want to delete all the control characters from my file using linux bash commands. There are some control characters like EOF (0x1A) especially which are causing the problem when I load my file in another software. I want to delete this. Here is what I have tried so far: this will list all the control characters: ``` cat -v -e -t file.txt | head -n 10 ^A+^X$ ^A1^X$ ^D ^_$ ^E-^D$ ^E-^S$ ^E1^V$ ^F%^_$ ^F-^D$ ^F.^_$ ^F/^_$ ^F4EZ$ ^G%$ ``` This will list all the control characters using grep: ``` $ cat file.txt | head -n 10 | grep '[[:cntrl:]]' + 1 - - 1 % - . / ``` matches the above output of cat command. Now, I ran the following command to show all lines not containing control characters but it is still showing the same output as above (lines with control characters) ``` $ cat file.txt | head -n 10 | grep '[^[:cntrl:]]' + 1 - - 1 % - . / ``` here is the output in hex format: ``` $ cat file.txt | head -n 10 | grep '[[:cntrl:]]' | od -t x2 0000000 2b01 0a18 3101 0a18 2004 0a1f 2d05 0a04 0000020 2d05 0a13 3105 0a16 2506 0a1f 2d06 0a04 0000040 2e06 0a1f 2f06 0a1f 0000050 ``` as you can see, the hex values, 0x01, 0x18 are control characters. I tried using the tr command to delete the control characters but got an error: ``` $ cat file.txt | tr -d "\r\n" "[:cntrl:]" >> test.txt tr: extra operand `[:cntrl:]' Only one string may be given when deleting without squeezing repeats. Try `tr --help' for more information. ``` If I delete all control characters, I will end up deleting the newline and carriage return as well which is used as the newline characters on windows. How do I delete all the control characters keeping only the ones required like "\r\n"? Thanks.