bash.word-splitting.rme

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..                               Word Splitting                               ..
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# ------------------------------- INTRODUCTION ------------------------------- #

   Word splitting only occurs if (and only if!) any of the following expansions
   are performed: 
      - Parameter expansion
      - Command substitution
      - Arithmetic expansion
   
   Bash will scan the results of the above expansions for special IFS chars
   that mark word boundaries. This is only done on results that are
   _NOT_ double-quoted!


                 -> *> #>   INTERNAL FIELD SEPARATOR    <# <* <-

   The IFS variable holds the characters that Bash regards as word boundaries.

   The default characters are (in order): 
      - <space>
      - <tab>
      - <newline>

   The default characters are assumed when IFS is *unset*.
   When IFS is *empty* (nullstring), no word splitting is performed at all.


                 -> *> #>           BEHAVIOR           <# <* <-

   The results of the expansions mentioned above are scanned for IFS
   characters. If one or more (in a sequence) of them is found, the expansion
   result is split at these positions into multiple words.

   Again, this doesn't happen when expansion results are double-quoted.

   When a null-string (e.g. something that expanded into nothing) is found,
   it is removed unless it is quoted (' ' or " ").

   Again note: Without any expansion beforehand, Bash won't perform word
   splitting! In this case, the initial token parsing is soley responsible.


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