ffinfo

ffinfo dumps a list of all current file format plug-ins and their locations. Here's some sample output:

[I] In directory /usr/local/VoxBo/etc/fileformats:
[I]   filetype "Penn/GE .im" (da4) found in file ff_da.o
[I]   filetype "GE I.XXX" (ge3) found in file ff_ge.o
[I]   filetype "BrainVoyager(tm) VMP" (vmp) found in file ff_vmp3d.o
[I] In directory .:
[I]   filetype "VoxBo CUB1" (cub1) found in file built-in
[I]   filetype "VoxBo TES1" (tes1) found in file built-in
[I]   filetype "VoxBo REF1" (ref1) found in file built-in
[I]   filetype "Analyze 3D" (img3d) found in file built-in
[I]   filetype "Analyze 4D" (img4d) found in file built-in
[I]   filetype "Analyze 4D directory" (imgdir) found in file built-in
[I]   filetype "DICOM 3D" (dcm3d) found in file built-in
[I]   filetype "DICOM 4D" (dcm4d) found in file built-in
[I]   filetype "NIfTI 3D" (n13d) found in file built-in
[I]   filetype "NIfTI 4D" (n14d) found in file built-in