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# Sets up auto-logging to a log file in the current directory
# using the specified logFileTag (arg 1) in the log file name.
auto_log() {
local logFileTag="$1"
if [[ "$logFileTag" != "" ]]; then
local logFilePath="./autoLog_${logFileTag}.log"
echo_se ".. logging to $logFilePath"
exec 1> >(tee "$logFilePath") 2>&1
else
echo_se "** ERROR in autoLogauto_log: no logFile argument provided"
exit 255
fi
} |
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Executing: | Code Block |
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| ~/workshop/step_02.sh testAutolog test1 |
produces this output: | Code Block |
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.. logging to ./autoLog_test1.log
1) Call stdStreams with output and error text:
to standard output: 'text for standard output'
to standard error: 'text for standard error'
2) Capture echo output in a variable and display it:
echo output was:
text for standard output
3) Call echo_se with error text:
text for standard error
4)Capture echo_se function output in a variable and display it:
text for standard error
echo_se output was: '' |
|
Why are both standard error and standard output text strings displayed in segment 1) when stdStreams is called?
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Because stdStreams echo's to both standard error and standard output in the current execution environment, where both are directed to the terminal by auto-logging. |
Why does the $output variable contain the outTxt the output text in 2) when echo is called with output being captured ?
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Because backtick evaluation replaces the command in backticks ( `...` ) with the command's standard output. |
...
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The log file produced is autoLog_test1.log, written to the current directory in force when step_02.sh was called. This name is based on the logFileTag we specified as "test1". Its contents (below) are nearly the same as when ~/workshop/step_02.sh testAutoLog test1 is called, except that the ".. logging to ./autoLog_test1.log" line is not reported, since because that was written before automatic logging was started. | Code Block |
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1) Call stdStreams with output and error text:
to standard output: 'text for standard output'
to standard error: 'text for standard error'
2) Capture echo output in a variable and display it:
echo output was:
text for standard output
3) Call echo_se with error text:
text for standard error
4)Capture echo_se function output in a variable and display it:
text for standard error
echo_se output was: '' |
|
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