The EPICS_TIMEZONE environment parameter provided time-zone +information for the IOC's locale in the old ANSI format expected by VxWorks for +its TIMEZONE environment variable, and can also used by RTEMS to set +its TZ environment variable. However the TIMEZONE value has to +be updated every year since it contains the exact dates of the daylight-savings +time changes. The Posix TZ format that RTEMS uses contains rules that for +calculating those dates, thus its value would only need updating if the rules +(or the locale) are changed.
+ +This release contains changes that replace the EPICS_TIMEZONE +environment parameter with one called EPICS_TZ and a routine for +VxWorks that calculates the TIMEZONE environment variable from the +current TZ value. This routine will be run once at start-up, when the +EPICS clock has synchronized to its NTP server. The calculations it contains +were worked out and donated to EPICS by Larry Hoff in 2009; it is unforunate +that it has taken 10 years for them to be integrated into Base.
+ +The default value for the EPICS_TZ environment parameter is set in +the Base configure/CONFIG_SITE_ENV file, which contains example settings for +most EPICS sites that use VxWorks, and a link to a page describing the Posix TZ +format for any locations that I missed.
+ +If a VxWorks IOC runs continuously without being rebooted from December 31st +to the start of daylight savings time the following year, its TIMEZONE +value will be wrong as it was calculated for the previous year. This only +affects times that are converted to a string on the IOC however and is easily +fixed; just run the command tz2timezone() on the VxWorks shell and the +calculation will be redone for the current year. IOCs that get rebooted at least +once before the start of summer time will not need this to be done.
+Bruno Martins reported a problem with the CA client library at shutdown in a