-/bin/sh vs /bin/sh
 

What is the significance of the - when executing something in an inittab file? For instance:

::askfirst:-/bin/sh

vs

::askfirst:/bin/sh

Once upon a time I knew the answer, but it is hidden in some dark corner of my mind from which there seems to be no return and I'm not having much luck googling it. :)

I can't see any reference to the - character in any inittab manual pages. However, using a + character will cause init to do utmp/wtmp housekeeping.

I believe it prevents the changing of the flags in sh. This would be useful in setting $1 to -. Using + rather than - causes these flags to be turned off.

Thanks