Name
USE_DOUBLE_FORK
Synopsis
When sendmail forks a copy of itself to process a queue, it does so twice to prevent the creation of a zombie process. A zombie process is one that has lost its parent, and has not yet died. It continues to exist as though alive, yet it cannot be killed, hence it is a zombie.
This USE_DOUBLE_FORK compile-time macro is defined by default as
1
to enable the double fork to prevent zombies. In
the rare instance that you are porting to a new system, you can
redefine USE_DOUBLE_FORK like this:
APPENDDEF(`conf_sendmail_ENVDEF', `-DUSE_DOUBLE_FORK=0')
If you are running a precompiled sendmail
binary, you can use the -d0.10
debugging
command-line switch (-d0.10) to determine if
USE_DOUBLE_FORK is defined (if it appears in the list, it is
defined). New ports should be reported to
sendmail@sendmail.org so that they can be folded
into future releases.
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