localtime() for a different timezone

[bandeg]

Hello:

From a C program, how do I convert to local time when the TZ environment variable is set to UTC. (We want to keep our system in UTC, and only use local time in this instance.).

I can do:

#TZ=EST date

from the command line and get the proper result. I don't want to call use a system system("TZ=EST date") call from my C program fearing it will be too slow. And I want to avoid calculating time myself.

I have seen others setenv() to set the TZ environment variable from userspace then unsetenv() however, I worry that other processes (threads,etc) could ask for time when this is set to the local TZ.


Regards,
--B

[blinky]

Hav'nt got time to try and verify it but have a look at man pages for setenv and tzset (eg. set the TZ variable to something using setenv() and then call tzset() before calling localtime()).