The utilities are part of the SDIF library distribution and are built and installed automatically with the library. The selection specification can be appended to a filename. This way, there is no ambiguity with filenames containing the selection element markers below. You have to quote the whole selection if you want to use spaces on a Unix shell command line, however. The order of the 6 possible elements is not significant.
All specifications can be comma-separated lists of values .
Beware that column selections can produce invalid SDIF output in terms of the description types. It is useful to do this for external analysis of the data in an SDIF file, however. SDIF tools should check if it is allowed to select columns. If one of the five selections is not specified, all data is extracted. The selection can be made using an SDIF Select Specification appended to the input file, or by various flags on the command line.