JK> Can anyone post some sample code on how to read enviorent vars from
 JK> the current enviorment,  and if possible how to modify them?
To read the current environment, use the Standard C++ library function 
getenv().  There is no Standard C++ library function to modify the 
environment, *BUT* ...
 JK> The system I am working with is HP-UX 10.20 but would also like the
 JK> code to work with a Linux system.
... since you are targetting systems that both attempt to be compliant with 
the POSIX standard (ISO IEC 9445-1:1993), then you can almost certainly use 
putenv().  Some unix C libraries also support setenv() and unsetenv().
As always on a unix or linux system, the man pages are your friends (assuming 
you know where to look -- which you now do).
 ¯ JdeBP ®
--- FleetStreet 1.19 NR
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