If opening the output file for writing is not possible - e.g. because the user doesn't have sufficient privileges, then sort issues an error. The problem is that the whole - then useless - computation is already done.
In the following little example, it took ~15s to sort the data, and then to realize that it can't write the result: $ time seq 1000000 | src/sort --random-sort -o /cantwritehere src/sort: open failed: /cantwritehere: Permission denied real 0m14.955s user 0m14.936s sys 0m0.042s I'd have expected sort to give the error immediately after startup instead of wasting time for sorting. Shouldn't sort open the outfile right at the beginning (unless in==out), or is this behavior required by some standard? Have a nice day, Berny
