I have a block of text i'd like to change up:
^@^A^@jfits^@^A^@pin^@^A^@sadface^@^A^@secret^@^A^@test^@^A^@tools^@^A^@ttttfft^@^A^@tty^@^A^@vuln^@^A^@yes^@^
using sed i'd like to remove all the ^@^A^ (and variations of those chars) with a few spaces.
I tried:
cat -A file | sed 's/\^A\^\@/ /'
but thats obviously wrong, can someone help?
if you can enumerate the allowed characters then you can do something like
sed -e 's/[^a-zA-Z0-9]/ /g'
which will replace everything not in the set of alphanumeric characters with a space.
If you just want to replace all 'non-printable' characters with spaces then you can use a character class[1] with
sed -e 's/[^[:print:]]/ /g'
some older versions of sed may not support this syntax though but it is standardized in the unix specification so you should not feel guilty for using it.[2]
[1] http://sed.sourceforge.net/sedfaq3.html
[2] http://pubs.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap09.html#tag_09_03
It looks like ^A is not two characters, but in fact just one control character. So you should write something like \x01 instead.
Anyway, there are three character ranges, \x00-\x1f are control characters, \x20-\x7f are ascii, and others are... something that depends on encoding.
I don't know sed well, but if you want ascii only, that's how I would've done it in perl:
head /dev/urandom | perl -pe 's/[^\x20-\x7f]/ /gi'
If only replace ^A and ^@, you can use this:
sed 's/[\x01\x0]/ /g' file
Then I find more similar answers in SO which already discussed.
https://superuser.com/questions/75130/how-to-remove-this-symbol-with-vim
