| 1 | #!/bin/sh
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| 2 |
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| 3 | # 'trap' is a very useful tool that I've been using on the exercises
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| 4 | # where I said you didn't have to worry about deleting the created file.
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| 5 | #
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| 6 | # $ trap command SIGNAL
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| 7 | #
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| 8 | # For example, in your tests/ files, many will have trap statements
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| 9 | #
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| 10 | # $ cleanup() {
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| 11 | # $ [ -f "file" ] && rm file
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| 12 | # $ }
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| 13 | # $ trap cleanup EXIT
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| 14 | #
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| 15 | # exit is the signal for trap to call cleanup(). Below are the different
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| 16 | # signals that trap detects in standard POSIX
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| 17 | #
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| 18 | # $ trap command EXIT # catches both exit 1 and exit 0
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| 19 | # $ trap command INT # catches ctrl+c kills
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| 20 | # $ trap command TERM # catches a signal terminate, like 'kill'
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| 21 | # $ trap command INT EXIT # catches different instances
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| 22 | #
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| 23 | # You don't have to call functions when running trap, you can run
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| 24 | # commands in the same line
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| 25 | #
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| 26 | # $ trap 'echo "Exiting.."; exit' TERM
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| 27 | #
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| 28 | # Below is a simple creation of a file, write a trap line that prints
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| 29 | # out "Removing..." and removes the file
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| 30 |
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| 31 | touch file.txt
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| 32 | echo "kill me" > file.txt
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