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ファイルに次の値があるとします。/usr/bin/ls

${file##/*/}

次のコマンドの後、出力はどのようになりますlsか?

##..の意味が理解できないようです。

ここで何が起きてるの?

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1 に答える 1

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/*/この式は、 の値の先頭からパターンに一致するものをすべて削除しますfile

man bash:

   ${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  pat‐
          tern  (the  ``##''  case)  deleted.  If parameter is @ or *, the
          pattern removal operation is applied to each positional  parame‐
          ter in turn, and the expansion is the resultant list.  If param‐
          eter is an array variable subscripted with @ or *,  the  pattern
          removal  operation  is  applied  to  each member of the array in
          turn, and the expansion is the resultant list.
于 2013-09-07T16:17:28.790 に答える