Reads stdin, and outputs each line only once - without sorting ahead of time. This does use more memory than your system's sort utility.
Thanks to the authors of:
awk '!x[$0]++' <file>
and the author of:
joinargs() { (local IFS="$1"; shift && echo "$*") }
and others, we can have a fast Linux or android.
IMPORTANT if you find a priority order problem in PATH you can push a path directory to the front without duplication as follows:
PATH=/bin:$PATH
then ...
Check duplication with:
echo $PATH|tr : '\n'|sort|uniq -d
Finally do a very neat line by line list of $PATH:
echo "${PATH//:/$'\n'}
The speed up is very noticeable for android, and builds on Linux Ubantu are much faster with make and scripts.
I will update the command on request. Timothy from SONY
Remove duplicate lines whilst keeping order and empty lines
Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?
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echo -e "aaa\nbbb\naaa"|awk \!'x[$0]++'
outputs aaa bbb not just "aaa"