On 11/2/17 7:03 AM, Michael F Gordon wrote: > Can anyone explain the following? > > tla19> set|grep FOOFOOFOO > tla19> if [ -d ${FOOFOOFOO:=""} ]; then echo YES;fi > YES > tla19> echo $BASH_VERSION > 4.4.12(1)-release
Greg is correct. This expands to [ -d ], which is true. There was an expansion bug in bash-4.1 that caused ${FOOFOOFOO:=""} to expand to the empty string, but that was fixed almost eight years ago as the result of http://www.austingroupbugs.net/view.php?id=221 Chet -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, UTech, CWRU c...@case.edu http://cnswww.cns.cwru.edu/~chet/