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|
case: daemon with monitor
=========================
main monitor worker
|
|-fork------
| \
| |
|-read----->|
| |
| |--fork-----
| | \
| | |
| |-read----->|
| | |
| | listen
| | |
| |<----write-|
| | |
| read-ok |
| | |
| | accept
| | |
|<----write-| |
| | |
read-ok |-waitpid-->|
| |
exit(0) v
case: daemon with monitor with listen-error
===========================================
main monitor worker
|
|-fork------
| \
| |
|-read----->|
| |
| |--fork-----
| | \
| | |
| |-read----->|
| | |
| | listen => error
| | |
| | exit(1)
| |
| read-fail
| |
| exit(1)
|
read-fail
|
exit(1)
case: daemon without monitor
============================
main worker
|
|-fork------
| \
| |
|-read----->|
| |
| listen
| |
|<----write-|
| |
| accept
| |
| v
read-ok
|
exit(0)
case: daemon without monitor with listen-error
==============================================
main worker
|
|-fork------
| \
| |
|-read----->|
| |
| listen => error
| |
| exit(1)
|
read-fail
|
exit(1)
|
