Bash globbing hidden files

bashwildcards

I'm trying the following globs in a bash shell:

$ ls -d .*
.  ..  .a  .ab
$ ls .a*
.a  .ab
$ ls .[!.]*
.a  .ab
$ ls .[!.]?*
.ab

Shouldn't the last expression mean "a dot followed by exactly one non-dot followed by zero or more characters"? Why does it fail to match .a?

Best Answer

You are mistaken. It means "a dot followed by exactly one non-dot followed by one character followed by zero or more characters". .a does not have enough characters to match it.

But really, just set dotglob.

Related Solutions

Bash – How/why does this globbing expression work

From man bash:

${parameter#word}
${parameter##word}

Remove matching prefix pattern. The word is expanded to produce a pattern just as in pathname expansion. If the pattern matches the beginning of the value of parameter, then the result of the expansion is the expanded value of parameter with the shortest matching pattern (the # case) or the longest matching pattern (the ## case) deleted.

Your pattern is *:*:*, and bash will try to remove the shortest matching prefix:

OK: for the first *:
DriveC-ReadBytesPerSec: for the second *:
and nothing for the last *, because it goes for the shortest match.

Compare:

$ # shortest match without surplus *
$ echo ${READRESULT#*:*:}
289283
$ # going for longest match now; the last * will swallow the number
$ echo ${READRESULT##*:*:*}

$ # longest match without the last *
$ echo ${READRESULT##*:*:}
289283
$ # no need to repeat *: because * matches everything before the last : anyway
$ echo ${READRESULT##*:}
289283

Bash – Configure bash globbing

Unfortunately, I must answer my own question. It was GLOBIGNORE. From the man page:

A colon-separated list of patterns defining the set of filenames to be ignored by pathname expansion. If a filename matched by a pathname expansion pattern also matches one of the patterns in GLOBIGNORE, it is removed from the list of matches.

Best Answer

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Bash – How/why does this globbing expression work

Bash – Configure bash globbing

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