list_image_info --per-volume for dynamic image is blank

list_image_info --per-volume dynamicXcat.txt

being dynamicXcat.txt a multi file, prints nothing but blank.

list_image_info --all dynamicXcat.txt

works though.

the multi file reads:

Multi :=
  total number of data sets := 15
  data set[1] := dynamicXcat_840_1050.hv
  data set[2] := dynamicXcat_1050_1260.hv
  data set[3] := dynamicXcat_1260_1470.hv
  data set[4] := dynamicXcat_1470_1680.hv
  data set[5] := dynamicXcat_1680_1890.hv
  data set[6] := dynamicXcat_1890_2100.hv
  data set[7] := dynamicXcat_2100_2310.hv
  data set[8] := dynamicXcat_2310_2520.hv
  data set[9] := dynamicXcat_2520_2730.hv
  data set[10] := dynamicXcat_2730_2940.hv
  data set[11] := dynamicXcat_2940_3150.hv
  data set[12] := dynamicXcat_3150_3360.hv
  data set[13] := dynamicXcat_3360_3570.hv
  data set[14] := dynamicXcat_3570_3780.hv
  data set[15] := dynamicXcat_3780_3990.hv
end :=

and each of the interfile images has a header like the following, but only changed the name of data file, and the relative start time.

!INTERFILE  :=
originating system := Discovery 600
!version of keys := STIR4.0
name of data file := dynamicXcat_2310_2520.v
!GENERAL DATA :=
!GENERAL IMAGE DATA :=
!type of data := PET
imagedata byte order := LITTLEENDIAN
!PET STUDY (General) :=
!PET data type := Image
!number format := float
!number of bytes per pixel := 4
number of dimensions := 3
matrix axis label [1] := x
!matrix size [1] := 400
scaling factor (mm/pixel) [1] := 2.03642
matrix axis label [2] := y
!matrix size [2] := 400
scaling factor (mm/pixel) [2] := 2.03642
matrix axis label [3] := z
!matrix size [3] := 100
scaling factor (mm/pixel) [3] := 2.025
first pixel offset (mm) [1] := -407.2840
first pixel offset (mm) [2] := -407.2840
first pixel offset (mm) [3] := 0
number of time frames := 1
image duration (sec)[1] := 210
image relative start time (sec)[1] := 2310
number of energy windows := 1
energy window lower level[1] := 650
energy window upper level[1] :=  425
!END OF INTERFILE :=

Reproduce the two commands with the supplied multi-file description and interfile headers, then trace list_image_info's --per-volume handling for multi-file dynamic images. Done means --per-volume reports the volume information instead of producing blank output, while --all continues to work.