unknown timezone name in R strptime/as.POSIXct

Question

Where can I find a list of all legal time names for R function as.POSIXct?

as.POSIXct(\"1970-01-01\",tz=\"CST\") generates a warning that \

Answer 1

Couldn't find it in that location on my make but found a zipped version in a source directory. Here's a list of timezone abbreviations that appear at the top level of the zones.tab file:

CET, CST6CDT, Cuba, EET, EST, EST5EDT, Egypt, Eire, Factory, GB, GB-Eire, GMT,
GMT+0, GMT-0, GMT0, Greenwich, HST, Hongkong, Iceland, Iran, Israel, Jamaica, Japan,
Kwajalein, Libya, MET, MST, MST7MDT, NZ, NZ-CHAT, Navajo, PRC, PST8PDT, Poland, Portugal,
ROC, ROK, Singapore, Turkey, UCT, UTC, Universal, W-SU, WET, Zulu

There are also folders with continent/country names, which have more options such as the America/New_York example above.:

Africa/     Asia/       Canada/     Indian/
America/    Atlantic/   Chile/      Mexico/
Antarctica/ Australia/  Etc/        Pacific/
Arctic/     Brazil/     Europe/     US/

This was found in the /R-2.11.1/src/extra/tzone/zoneinfo.zip file.