Redirect only stderr to file

./4a_eval_affine.pl 4a_structure_test_sets/ 1 2> 4_result/4a_vienna_for_file_1.txt

Wordcount in a PDF (e.g. Dissertation)

 pdftotext thesis.pdf - | wc -w

Open and jump to line in vi

$ vi +99 some-file

The above opens some-file and go immediately to line 99.