setenv

I have been thinking a little about environment variables and have a few questions/observations. putenv(char *string); This call seems fatally flawed. Because it doesn't copy the passed string you can't call it with a local and there is no guarantee a heap allocated string won't be overwritten or accidentally deleted. Furthermore (though I haven't tested it), since one use of environment variables is to pass values to child's environment this seems useless if the child calls one of the exec*() functions. Am I wrong in that? The Linux man page indicates that glibc 2.0-2.1.1 abandoned the above

I need to export several variables such that they look like the following in the command line export ROS_HOSTNAME=xxx How do I use setenv() in c++ to achieve that? Thanks. From the setenv() manual entry: SYNOPSIS #include <stdlib.h> int setenv(const char *envname, const char *envval, int overwrite); DESCRIPTION The setenv() function shall update or add a variable in the environment of the calling process. The envname argument points to a string containing the name of an environment variable to be added or altered. The environment variable shall be set to the value to which envval points. The