I have a question about the exit status of 3dTrackID after an apparently successful run. 3dTrackID seemed to complete its tasks just fine, and I got my expected output, but it exited with exit status 1 rather than 0. Can anyone tell me why? When it exits with code 1, it interrupts my bash script, since I include the option 'set -o errexit'.

Here is my command and the output:

user@machine $ 3dTrackID -mode DET -dti_in dti_preprocessed/dti-afni -netrois dti_preprocessed/t2w_epi_mean-brain_mask.nii.gz -mask dti_preprocessed/t2w_epi_mean-brain_mask.nii.gz -logic OR -write_opts -do_trk_out -nifti -prefix dti_preprocessed/trackid_det

++ ROI logic type is: OR
++ Tracking mode: DET
*+ WARNING:   If you are performing spatial transformations on an oblique dset, 
  such as dti_preprocessed/t2w_epi_mean-brain_mask.nii.gz,
  or viewing/combining it with volumes of differing obliquity,
  you should consider running: 
     3dWarp -deoblique 
  on this and  other oblique datasets in the same session.
 See 3dWarp -help for details.
++ Oblique dataset:dti_preprocessed/t2w_epi_mean-brain_mask.nii.gz is 0.615803 degrees from plumb.

++ Number of ROIs in netw[0] = 1
++ No refset labeltable for naming things.
++ Oblique dataset:dti_preprocessed/t2w_epi_mean-brain_mask.nii.gz is 0.615803 degrees from plumb.
++ 
++ SEARCHING for files with prefix 'dti_preprocessed/dti-afni*'
++ Obtained 9 prefix-matching files to sort

++ SCALAR FINDINGS:
	++ Oblique dataset:dti_preprocessed/dti-afni_DT.nii.gz is 0.615803 degrees from plumb.
 'FA' ++ Oblique dataset:dti_preprocessed/dti-afni_FA.nii.gz is 0.615803 degrees from plumb.
 'L1' ++ Oblique dataset:dti_preprocessed/dti-afni_L1.nii.gz is 0.615803 degrees from plumb.
++ Oblique dataset:dti_preprocessed/dti-afni_L2.nii.gz is 0.615803 degrees from plumb.
 'L2' ++ Oblique dataset:dti_preprocessed/dti-afni_L3.nii.gz is 0.615803 degrees from plumb.
 'L3'  'MD' ++ Oblique dataset:dti_preprocessed/dti-afni_MD.nii.gz is 0.615803 degrees from plumb.
++ Oblique dataset:dti_preprocessed/dti-afni_V1.nii.gz is 0.615803 degrees from plumb.
++ Oblique dataset:dti_preprocessed/dti-afni_V2.nii.gz is 0.615803 degrees from plumb.
++ Oblique dataset:dti_preprocessed/dti-afni_V3.nii.gz is 0.615803 degrees from plumb.

++ Done with scalar search, found: 6 parameters (well, including internal RD calc)
	--> so will have 17 output data matrices.
++ Calculating RD

++ VECTOR FINDINGS:
	++ Oblique dataset:dti_preprocessed/dti-afni_V1.nii.gz is 0.615803 degrees from plumb.
'V1'	++ Oblique dataset:dti_preprocessed/dti-afni_V2.nii.gz is 0.615803 degrees from plumb.
'V2'	++ Oblique dataset:dti_preprocessed/dti-afni_V3.nii.gz is 0.615803 degrees from plumb.
'V3'	
++ With '-logic OR', the '-cut_at_rois' option will be automically turned off ('-uncut_at_rois').
++ Tracking progress count: start ...
++ Done tracking, tidying up outputs...
++ From tracking, net[0] has 149328 tracks.
++ Writing output (RPI, same as your input): dti_preprocessed/trackid_det ...

user@machine $ echo $?

1