31 lines
1002 B
Plaintext
31 lines
1002 B
Plaintext
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# According to this doc, && || have higher precedence than ; &.
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# See example below.
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# Precedence of ; is not a problem in practice. Precedence of & is.
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#
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#http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
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#
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#2.9.3 Lists
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#
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#An AND-OR list is a sequence of one or more pipelines separated by
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#the operators "&&" and "||" .
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#
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#A list is a sequence of one or more AND-OR lists separated by the operators
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#';' and '&' and optionally terminated by ';', '&', or <newline>.
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#
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#The operators "&&" and "||" shall have equal precedence and shall be
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#evaluated with left associativity. For example, both of the following
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#commands write solely bar to standard output:
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#
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# false && echo foo || echo bar
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# true || echo foo && echo bar
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#
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#A ';' or <newline> terminator shall cause the preceding AND-OR list
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#to be executed sequentially; an '&' shall cause asynchronous execution
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#of the preceding AND-OR list.
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echo First && sleep 0.2 && echo Third &
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sleep 0.1
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echo Second
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wait
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echo Done
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