On Thu, May 04, 2017 at 02:42:00PM +1000, Andrew McGlashan wrote:
That's okay, so long as there is at least one target file, otherwise it fails.
I've added a test before now and dropped the ls in the for.
or you could just set nullglob in the script.
From the bash man page:
nullglob If set, bash allows patterns which match no files (see Pathname Expansion above) to expand to a null string, rather than themselves. e.g. $ for i in *.doesnotexist ; do echo $i ; done *.doesnotexist $ shopt -s nullglob $ for i in *.doesnotexist ; do echo $i ; done $ Note that this only affects interpretation of glob patterns, not fixed strings. so 'for i in 1 2 3 4 5; ...' still works as expected because there aren't any glob/wildcard characters in it. you can put the nullglob setting and for the loop in a different scope (e.g. a sub-shell or a function) if you need to avoid nullglob having unwanted side-effects on other parts of the script. but, really, why write a 58 line shell script when a oneliner rename command (or 2 or 3 lines when reformatted for readability) is all that's needed? or one of the many similar utilites to do this extremely common task (most of which are both harder to use and less functional than the perl rename tool). craig ps: the previously mentioned Bash Pitfalls and the Bash FAQ at the same site are, IMO, **ESSENTIAL** reading for anyone wanting or needing to write bash scripts. also useful for other sh dialects. http://mywiki.wooledge.org/BashPitfalls http://mywiki.wooledge.org/BashFAQ I also highly recommend the Unix & Linux Stack Exchange site for anything to do with shell, awk, sed, etc scripting. Searching there will almost certainly find good solutions for whatever you're trying to do and if not, you can always ask your own question and get a good answer in short order. https://unix.stackexchange.com/ -- craig sanders <cas@taz.net.au>