emanuele6 1658629885 learn `kill -9 -- "$pid"' or `kill -USR1 -- "$pid"' will not work in dash (even though they should according to POSIX): when the first argument of kill(1) starts with a "-" followed by a valid signame or signum, dash will not handle options, and will just use the rest of the arguments as jobspecs (including `--' which will cause an error). Instead of `kill -USR1 --', you can use `kill -s emanuele6 1658629938 forget emanuele6 1658630245 learn `kill -9 --' and `kill -USR1 --' will not work in dash (even though they should according to POSIX): when the first argument of `kill' is "-" followed by a signame/signum, dash just treats the rest of the arguments as jobspecs (including --) instead of interpreting options. Use `kill -s USR1 --' instead. If you need to use a signum, the only solution is to remove --. emanuele6 1676663909 forget emanuele6 1676664019 learn `kill -9 --' and `kill -USR1 --' will not work in dash (even though they should according to POSIX): when the first argument of `kill' is "-" followed by a signame/signum, dash just treats the rest of the arguments as jobspecs (including --) instead of interpreting options. Use `kill -s USR1 --' instead. If you must use a signal number, you can use `kill -s "$(kill -l -- "$signum")" emanuele6 1676664034 forget emanuele6 1676664081 learn `kill -9 --' and `kill -USR1 --' will not work in dash (even though they should according to POSIX): when the first argument of `kill' is "-" followed by a signame/signum, dash just treats the rest of the arguments as jobspecs (including --) instead of interpreting options. Use `kill -s USR1 --' instead. Or, if you need to use a signal number, `kill -s "$(kill -l -- "$signum")" --'. emanuele6 1676664328 forget emanuele6 1676664451 learn `kill -9 --' and `kill -USR1 --' will not work in dash (even though they should according to POSIX): when the first argument of `kill' is "-" followed by a signame/signum, dash treats just the rest of the arguments (including --) as jobspects. Use `kill -s USR1 --' instead. Or, if you need to use a signal number, `kill -s "$(kill -l -- "$(( signum + 128 ))")" --'.