BASH: unescape string
POSIX sh provides printf %b for just this purpose:
s='some\nstring\n...'printf '%b\n' "$s"...will emit:
somestring...More to the point, the APPLICATION USAGE section of the POSIX spec for echo explicitly suggests using printf %b for this purpose rather than relying on optional XSI extensions.
As you observed, echo does not solve the problem:
$ s="some\nstring\n..."$ echo "$s"some\nstring\n...You haven't mentioned where you got that string or which escapes are in it.
Using a POSIX-compliant shell's printf
If the escapes are ones supported by printf, then try:
$ printf '%b\n' "$s"somestring...Using sed
$ echo "$s" | sed 's/\\n/\n/g'somestring...Using awk
$ echo "$s" | awk '{gsub(/\\n/, "\n")} 1'somestring...
If you have the string in a variable (say myvar), you can use:
${myvar//\\n/$'\n'}For example:
$ myvar='hello\nworld\nfoo'$ echo "${myvar//\\n/$'\n'}"helloworldfoo$ (Note: it's usually safer to use printf %s <string> than echo <string>, if you don't have full control over the contents of <string>.)