When I was compiling Zabbix agent for Windows, I got a following message.
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..\..\..\src\libs\zbxsys\mutexs.c(71) : warning C4013: 'strerror_from_system' undefined; assuming extern returning int
The compiler encountered a call to an undefined function.
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Zabbix uses 'strerror_from_system()' function without including log.h in mutexs.c.
If CreateMutex() failed, Zabbix agent will crash.
Following line is needed in mutexs.c.
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#include "log.h"
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