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EXPANSION

Expansion is performed on the command line after it has been split into words. There are seven kinds of expansion performed: .IR "brace expansion" , .IR "tilde expansion" , .IR "parameter and variable expansion" , .IR "command substitution" , .IR "arithmetic expansion" , .IR "word splitting" , and .IR "pathname expansion" .

The order of expansions is: brace expansion, tilde expansion, parameter, variable and arithmetic expansion and command substitution (done in a left-to-right fashion), word splitting, and pathname expansion.

On systems that can support it, there is an additional expansion available: process substitution\fP.

Only brace expansion, word splitting, and pathname expansion can change the number of words of the expansion; other expansions expand a single word to a single word. The only exceptions to this are the expansions of "$@\fP" and "${\fPname\fP[@]}\fP" as explained above (see .SM .BR PARAMETERS ).

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