SETDIR sets the default directories and extensions of files storing images, spectra, color maps, etc. You can see the default values with the command PRINT DIRECTORIES. See the section FILES (type HELP FILES if you're on a terminal) for information about default directories and extensions. See also the command CD to change the current working directory (./) on a UNIX system.
The DIR word gives the default directory for the type of object specified by the code, and the EXT word gives the extension for that type of object. An example of a default extension is that for '.fits' for images. An example of a default directory is 'ccd/spec' for spectra. You must specify either the directory or the extension or both with SETDIR. If the extension is not blank, it must include a period as its first character: For example, '.xyz' is a valid extension, while 'flk' is not.
The 'code' gives the directory which is being set or changed. The code is derived from the type of object in the directory you are specifying. You must type at least the first two letters of the code:
| Directory | Code | Abbrev | Notes |
| Images | IMAGES | IM | (user defined, usually ./) |
| Spectra | SPECTRA | SP | (archaic, use IMAGES) |
| Procedures | PROCEDURES | PR | (user defined) |
| Data Files | DATA | DA | (user defined, usually ./) |
| DAOPHOT files | PHOTOMETRY | PH | (user defined) |
| Flux calibration files | FLUX | FL | (assigned by system) |
| Wavelength files | WAVE | WA | (assigned by system) |
| Color maps | COLOR | CO | (assigned by system) |
Examples: Suppose you see with PRINT DIR that the default directory for CCD
spectra is ccd/spec and the default extension is '.fits'