Find highest numbered filename in a directory where names start with digits

bash shell sed ls
Jake picture Jake · Oct 19, 2009 · Viewed 14.8k times · Source

I have a directory with files that look like this:

001_something.php  002_something_else.php
004_xyz.php        005_do_good_to_others.php

I ultimately want to create a new, empty PHP file whose name starts with the next number in the series.

LIST=`exec ls $MY_DIR | sed 's/\([0-9]\+\).*/\1/g' | tr '\n' ' '`

The preceding code gives me a string like this:

LIST='001 002 004 005 '

I want to grab that 005, increment by one, and then use that number to generate the new filename. How do I do that in BASH?

Answer

bmb picture bmb · Oct 19, 2009

Do you need the whole LIST?

If not

LAST=`exec ls $MY_DIR | sed 's/\([0-9]\+\).*/\1/g' | sort -n | tail -1`

will give you just the 005 part and 

printf "%03d" `expr 1 + $LAST`

will print the next number in the sequence.

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