13.2 Command-Line Syntax

All parameters for NCBI-BLAST programs are single letters and must be preceded by a single dash. Unlike many common Unix programs, the parameters for NCBI programs are never concatenated. All parameters may take arguments, including those that operate as true/false (T/F) switches. For such switches, the T/F is case-insensitive, and the argument may be omitted, in which case the switch is set to T. Finally, the space between the parameter and the argument is optional. The following commands are all identical.

formatdb -i db -o T -V t
formatdb -i db -o -V
formatdb -idb -ot -VT
formatdb -idb -o -V

The following command, however, is illegal because it tries to set -o to a value of V.

formatdb -idb -oV