It's "kill -QUIT", not "kill -SIGQUIT". (But "kill -3" works too.)

anamexis · on June 16, 2017

At least for GNU, it is valid to prefix the signal specification with SIG.

cf. https://github.com/coreutils/coreutils/blob/master/src/opera...

Appears to be the case for BSD as well: https://github.com/freebsd/freebsd/blob/master/bin/kill/kill...

jwilk · on June 16, 2017

The SIG prefix doesn't work in dash (the default shell in Debian).

POSIX¹ says:

An early proposal also required symbolic signal_names to be recognized with or without the SIG prefix. Historical versions of kill have not written the SIG prefix for the -l option and have not recognized the SIG prefix on signal_names. Since neither applications portability nor ease-of-use would be improved by requiring this extension, it is no longer required.

¹ http://pubs.opengroup.org/onlinepubs/9699919799/utilities/ki...