Interesting question. I tried to use xargs for this and I found a way. Try this: seq 10 | xargs -i –max-procs=4 bash -c “echo start {}; sleep 3; echo done {}” –max-procs=4 will ensure that no more than four subprocesses are running at a time. The output will look like this: start 2 start … Read more
Yes, but don’t do that. Use an array instead. If you still insist on doing it that way… $ foo1=123 $ bar=foo1 $ echo “${!bar}” 123
You need to use single quotes to prevent interpolation happening in your calling shell. $ bash -c ‘echo arg 0: $0, arg 1: $1’ arg1 arg2 arg 0: arg1, arg 1: arg2 Or escape the variables in your double-quoted string. Which to use might depend on exactly what you want to put in your snippet … Read more
Simply don’t put whole commands in variables. You’ll get into a lot of trouble trying to recover quoted arguments. Also: Avoid using all-capitals variable names in scripts. It is an easy way to shoot yourself in the foot. Don’t use backquotes. Use $(…) instead; it nests better. #! /bin/bash if [ $# -ne 2 ] … Read more
find your/folder -type f -mtime +13 -exec rm {} \;
There are a few really simple methods: pgrep procname && echo Running pgrep procname || echo Not running killall -q -0 procname && echo Running pidof procname && echo Running
From a very quick search, it looks like your error is related to the following issue : JENKINS-33708 The main cause looks like the sh step is not supported on the Windows. You may use bat or install Cygwin for instance. Nevertheless two solutions were proposed in the previous link, suggesting you to do the … Read more
Using grep is overkill, and can cause trouble if you’re searching for anything that happens to include RE metacharacters. This problem can be solved perfectly well with bash’s builtin [[ command: if [[ “:$PATH:” == *”:$HOME/bin:”* ]]; then echo “Your path is correctly set” else echo “Your path is missing ~/bin, you might want to … Read more
If you want to wait for jobs to finish, use wait. This will make the shell wait until all background jobs complete. However, if any of your jobs daemonize themselves, they are no longer children of the shell and wait will have no effect (as far as the shell is concerned, the child is already … Read more
You can use the same option multiple times and add all values to an array. For the very specific original question here, Ryan’s mkdir -p solution is obviously the best. However, for the more general question of getting multiple values from the same option with getopts, here it is: #!/bin/bash while getopts “m:” opt; do … Read more