Let’s say you’ve got a terminal open and you want to sort the contents of a file before you email it to a friend. The file can contain anything and it could be of any length, it doesn’t matter. What do you do?
The obvious answer is to use sort. Sorting the file is as easy as sort myfile – except it doesn’t actually sort the file, it sorts the *contents* of the file and dumps them to the command line (via stdout). So how do you sort the file “in-place,” so-to-speak? Again, the obvious answer would be sort myfile > myfile,1 redirecting the output of the sort command back to the file you want to ultimately send sorted.
Don’t do this! ↩