The library routines described on this page provide the application access to the system network configuration database, /etc/netconfig. The getnetconfig function returns a pointer to the current entry in the netconfig database, formatted as a "struct netconfig". Successive calls will return successive netconfig entries in the netconfig database. The getnetconfig function can be used to search the entire netconfig file. The getnetconfig function returns NULL at the end of the file. The handlep argument is the handle obtained through setnetconfig.
A call to setnetconfig has the effect of "binding" to or "rewinding" the netconfig database. The setnetconfig function must be called before the first call to getnetconfig and may be called at any other time. The setnetconfig function need not be called before a call to getnetconfigent. The setnetconfig function returns a unique handle to be used by getnetconfig.
The endnetconfig function should be called when processing is complete to release resources for reuse. The handlep argument is the handle obtained through setnetconfig. Programmers should be aware, however, that the last call to endnetconfig frees all memory allocated by getnetconfig for the "struct netconfig" data structure. The endnetconfig function may not be called before setnetconfig.
The getnetconfigent function returns a pointer to the netconfig structure corresponding to netid. It returns NULL if netid is invalid (that is, does not name an entry in the netconfig database).
The freenetconfigent function frees the netconfig structure pointed to by netconfigp (previously returned by getnetconfigent).
The nc_perror function prints a message to the standard error indicating why any of the above routines failed. The message is prepended with the string msg and a colon. A newline character is appended at the end of the message.
The nc_sperror function is similar to nc_perror but instead of sending the message to the standard error, will return a pointer to a string that contains the error message.
The nc_perror and nc_sperror functions can also be used with the NETPATH access routines defined in getnetpath(3).
The setnetconfig function returns a unique handle to be used by getnetconfig. In the case of an error, setnetconfig returns NULL and nc_perror or nc_sperror can be used to print the reason for failure.
The getnetconfig function returns a pointer to the current entry in the netconfig database, formatted as a "struct netconfig". The getnetconfig function returns NULL at the end of the file, or upon failure.
The endnetconfig function returns 0 on success and -1 on failure (for example, if setnetconfig was not called previously).
On success, getnetconfigent returns a pointer to the "struct netconfig" structure corresponding to netid; otherwise it returns NULL.
The nc_sperror function returns a pointer to a buffer which contains the error message string. This buffer is overwritten on each call. In multithreaded applications, this buffer is implemented as thread-specific data.