How to view last 5 lines from last created/modified file?

Question

Every day I have to take backup and update the status to support teams at particular time for which I need to check last 5 lines of last created/modified *.aff file in a directory and update them.

Can anyone please let me know how to view last 5 lines from last modified file (particular extension) in linux as with *.aff file? other files are also created e.g. *.log, etc.

Answer 1

With the zsh shell:

tail -n 5 ./*.aff(D.om[1])

With other shells, it's quite difficult to come up with something reliable if you don't want to make assumptions on what file names may contain.

For instance, the bash equivalent, if you're on a recent GNU system would be:

find . -maxdepth 1 -name '*.aff' -type f -printf '%T@:%p\0' |
  sort -rzn |
  sed -zn 's/[^:]*://p;q' |
  xargs -r0 tail -n 5

Or:

find . -maxdepth 1 -name '*.aff' -type f -printf '%T@/%p\0' |
  sort -rzn | (IFS=/ read -rd '' mtime file && tail -n 5 "$file")

Answer 2

Assuming file names don't contain newline characters and that all the *.aff files are regular files:

ls -t1d -- *.aff | head -n 1

gives you the name of the most recently modified .aff-file. If you want the last 5 lines just do:

tail -n 5 -- "$(ls -t1d -- *.aff | head -n 1)"

Answer 3

Another safe approach that should work on any GNU system and Busybox:

tail -n5 "$(stat -c "%Y %n" ./* | 
    sort -nk1,1 | cut -d ' ' -f 2- | tail -n1)"

That will work on most things but if your file names can contain newlines, use this instead (GNU only, still breaks if your files end in newlines):

tail -n5 "$(stat --printf "%Y %n\0" ./* | 
    sort -rznk1,1 | sed -zn 's/[0-9]\+ //p;q')"