mirror of https://github.com/n-hys/bash.git
33 lines
1.0 KiB
Plaintext
33 lines
1.0 KiB
Plaintext
# This program is free software: you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation, either version 3 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program. If not, see <http://www.gnu.org/licenses/>.
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#
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# tests of return value inversion
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# placeholder for future expansion
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# user subshells (...) did this wrong in bash versions before 2.04
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! ( echo hello | grep h >/dev/null 2>&1 ); echo $?
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! echo hello | grep h >/dev/null 2>&1 ; echo $?
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! true ; echo $?
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! false; echo $?
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! (false) ; echo $?
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! (true); echo $?
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! true | false ; echo $?
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! false | true ; echo $?
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! (true | false) ; echo $?
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! (false | true) ; echo $?
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