cnet v2.0.5

simulation model

topology files
cmdline options
the API



cnet's checksum and miscellaneous functions


Checksum functions

int checksum_internet(unsigned short *addr, int nbytes)

unsigned short checksum_ccitt(unsigned char *addr, int nbytes)

unsigned short checksum_crc16(unsigned char *addr, int nbytes)

unsigned int checksum_crc32(unsigned char *addr, int nbytes)

These four checksum functions each take a memory address and perform the specified checksum calculation on the indicated number of bytes starting from that address.


Miscellaneous functions

int CNET_read_keyboard(char *line, int *len)

Requests the specified maximum number of bytes from the keyboard buffer placing them in the address pointed to by line. On invocation, len will point to an integer indicating the maximum number of bytes that may be copied into line. On return, line will be NULL-byte terminated (and not include a newline) and the integer pointed to by len will contain strlen(line)+1.


int CNET_set_debug_string(CnetEvent ev, char *str)

Change the string on the indicated windowing debug button (for EV_DEBUG1..EV_DEBUG5) to str. If str is NULL or the empty string, the indicated button is removed.

Possible errors: ER_BADEVENT.

int CNET_set_time_of_day(long newsec, long newusec)

Change the node's notion of the wall-clock time of day. As nodeinfo should be considered a read-only structure, this is the only method to set time_of_day.sec and time_of_day.usec . (time_of_day.sec is the number of seconds since Jan. 1, 1970, and may be used in a call to ctime(3c)).

Possible errors: ER_BADARG.

cnet was written and is maintained by Chris McDonald (