mirror of https://github.com/tLDP/LDP
17 lines
530 B
Bash
17 lines
530 B
Bash
#!/bin/bash
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# usage-message.sh
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: ${1?"Usage: $0 ARGUMENT"}
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# Script exits here if command-line parameter absent,
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#+ with following error message.
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# usage-message.sh: 1: Usage: usage-message.sh ARGUMENT
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echo "These two lines echo only if command-line parameter given."
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echo "command-line parameter = \"$1\""
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exit 0 # Will exit here only if command-line parameter present.
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# Check the exit status, both with and without command-line parameter.
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# If command-line parameter present, then "$?" is 0.
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# If not, then "$?" is 1.
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