On /Desktop/a/ , there is a set of files:
DSCN1840.AVI00001.png DSCN1840.AVI00002.png DSCN1840.AVI00003.png DSCN1841.AVI00001.png What I would like is to have the following structure:
Desktop/a/DSCN1840/ DSCN1840.AVI00001.png DSCN1840.AVI00002.png DSCN1840.AVI00003.png Desktop/a/DSCN1841/ DSCN1841.AVI00001.png As a one-shot step, you could loop through all of the files and gather the desired subdirectory name; if that subdirectory doesn't already exist, create it; then move that file into that subdirectory:
for f in *.png do subdir=${f%%.*} [ ! -d "$subdir" ] && mkdir -- "$subdir" mv -- "$f" "$subdir" done The key part of this is the parameter expansion in ${f%%.*}, which says to remove the longest matching portion (%%) of a period followed by anything, which effectively strips off, for example, the .AVI00003.png portions of the filenames, leaving only the leading directory indicator.
