| 1 | #!/usr/bin/env bash
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| 2 |
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| 3 |
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| 4 | sleep_test() {
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| 5 | echo "Sleeping for 10 seconds in subshell of PID $$"
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| 6 | type sleep # external command
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| 7 |
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| 8 | # NOTE: Within a subshell, $$ returns the PID of the script, not the subshell!
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| 9 |
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| 10 | # process tree for dash and bash looks different.
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| 11 | #
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| 12 | # dash appears to run the first thing not in a subshell? Hm maybe I could do
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| 13 | # that too. But then global var references would be different.
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| 14 |
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| 15 | ( echo "PID $$"; sleep 10 ) | tee foo.txt
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| 16 | #( echo "PID $BASHPID"; sleep 10 )
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| 17 |
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| 18 | # This doesn't cause an extra subshell in bash.
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| 19 | ( sleep 10 )
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| 20 | }
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| 21 |
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| 22 | g=0
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| 23 |
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| 24 | myfunc() {
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| 25 | echo 'running myfunc'
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| 26 | g=1
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| 27 | }
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| 28 |
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| 29 | # Hm bash and dash both seem to behave the same here.
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| 30 | var_test() {
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| 31 | myfunc | tee _tmp/command-sub.txt
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| 32 | { g=2; echo brace; } | tee _tmp/command-sub.txt
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| 33 |
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| 34 | echo "g after pipeline: $g"
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| 35 | }
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| 36 |
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| 37 | #sleep_test "$@"
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| 38 |
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| 39 | var_test
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