It’s the other way around: */1 * * * * sudo /home/pi/coup/sensor.py >> /home/pi/sensorLog.txt 2>&1 2>&1 will redirect standard error (2) to standard output (1) which -in turn – was redirected to your log file. So, at the end, both stderr and stdout will go to your sensorLog.txt
TL;DR: Since you are using Bash specific features, your script has to run with Bash and not with sh: $ sh myscript.sh myscript.sh: 2: myscript.sh: Bad substitution $ bash myscript.sh ffmpeg -i bar.mp4 bar.mp3 ffmpeg -i foo.mp4 foo.mp3 See Difference between sh and Bash. To find out which sh you are using: readlink -f $(which … Read more
When using == or != in bash you can write: if [[ $t1 == *”$t2″* ]]; then echo “$t1 and $t2 are equal” fi Note that the asterisks go on the outside of the quotes and that the wildcard pattern must be on the right. For /bin/sh, the = operator is for equality only, not … Read more
To add a crontab job, type the following command at a UNIX/Linux shell prompt: $ sudo crontab -e Add the following line: 1 2 3 4 5 /path/to/script where 1: Minutes (0-59) 2: Hours (0-23) 3: Days (1-31) 4: Month (1-12) 5: Day of the week(1-7) /path/to/script – your own shell script In your case … Read more
Use git rev-parse –abbrev-ref HEAD to get the name of the current branch. Then it’s only a matter of simply comparing values in your script: BRANCH=”$(git rev-parse –abbrev-ref HEAD)” if [[ “$BRANCH” != “x” ]]; then echo ‘Aborting script’; exit 1; fi echo ‘Do stuff’;
This has been asked: Recursive batch rename With your example, you could go with: brew install rename find . -exec rename ‘s|foo|bar|’ {} +
Since read reads whitespace-delimited fields by default, a line containing only whitespace should result in the empty string being assigned to the variable, so you should be able to skip empty lines with just: [ -z “$line” ] && continue
For GNU date: date_222days_before_TodayYear=$(date –date=”222 days ago” +”%Y”) date_222days_before_TodayMonth=$(date –date=”222 days ago” +”%m”) date_222days_before_TodayDay=$(date –date=”222 days ago” +”%d”) For BSD date:: If you are using OS X or FreeBSD, use the following instead because BSD date is different from GNU date: date_222days_before_TodayYear=$(date -j -v-222d +”%Y”) date_222days_before_TodayMonth=$(date -j -v-222d +”%m”) date_222days_before_TodayDay=$(date -j -v-222d +”%d”) Source: BSD … Read more
Invoke bc with the -l option (to enable the math library) like so: $ echo ‘l(100)/l(10)’ | bc -l 2.00000000000000000000 Use the l function which is the natural log. Take the natural log of the number you are interested in then divide it by the natural log of 10.
Use: find . -name “*.t1” -exec bash -c ‘mv “$1” “${1%.t1}”.t2’ – ‘{}’ + If you have rename available then use one of these: find . -name ‘*.t1’ -exec rename .t1 .t2 {} + find . -name “*.t1” -exec rename ‘s/\.t1$/.t2/’ ‘{}’ +