DESCRIPTION
The routines described in this page provide the application access to the system network configuration database, /etc/netconfig, as it is "filtered" by the NETPATH environment variable (see environ(7)). See getnetconfig(3) for other routines that also access the network configuration database directly. The NETPATH variable is a list of colon-separated network identifiers. The getnetpath function returns a pointer to the netconfig database entry corresponding to the first valid NETPATH component. The netconfig entry is formatted as a "struct netconfig". On each subsequent call, getnetpath returns a pointer to the netconfig entry that corresponds to the next valid NETPATH component. The getnetpath function can thus be used to search the netconfig database for all networks included in the NETPATH variable. When NETPATH has been exhausted, getnetpath returns NULL.
A call to setnetpath "binds" to or "rewinds" NETPATH. The setnetpath function must be called before the first call to getnetpath and may be called at any other time. It returns a handle that is used by getnetpath.
The getnetpath function silently ignores invalid NETPATH components. A NETPATH component is invalid if there is no corresponding entry in the netconfig database.
If the NETPATH variable is unset, getnetpath behaves as if NETPATH were set to the sequence of "default" or "visible" networks in the netconfig database, in the order in which they are listed.
The endnetpath function may be called to "unbind" from NETPATH when processing is complete, releasing resources for reuse. Programmers should be aware, however, that endnetpath frees all memory allocated by getnetpath for the struct netconfig data structure.
RETURN VALUES
The setnetpath function returns a handle that is used by getnetpath. In case of an error, setnetpath returns NULL. The endnetpath function returns 0 on success and -1 on failure (for example, if setnetpath was not called previously). The nc_perror or nc_sperror function can be used to print out the reason for failure. See getnetconfig(3).
When first called, getnetpath returns a pointer to the netconfig database entry corresponding to the first valid NETPATH component. When NETPATH has been exhausted, getnetpath returns NULL.
SEE ALSO
getnetconfig(3), netconfig(5), environ(7)
