NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | FILES | ATTRIBUTES | SEE ALSO | BUGS | RESTRICTIONS
#include <netdb.h>struct protoent * getprotoent(void);
The getprotoent() , getprotobyname() , and getprotobynumber() functions each return a pointer to an object containing the broken-out fields of a line in the network protocol data base, /etc/protocols . The object has the following structure:
struct protoent { char* p_name; /* official name of protocol */ char** p_aliases; /* alias list */ int p_proto; /* protocol number */ };
The members of this structure are:
The official name of the protocol.
A zero terminated list of alternate names for the protocol.
The protocol number.
The getprotoent() function reads the next line of the file, opening the file if necessary.
The setprotoent() function opens and rewinds the file. If the stayopen flag is non-zero, the net data base will not be closed after each call to getprotobyname() or getprotobynumber() .
The endprotoent() function closes the file.
The getprotobyname() and getprotobynumber() functions sequentially search from the beginning of the file until a matching protocol name or protocol number is found, or until EOF is encountered (see RESTRICTIONS).
A
NULL
pointer (
0
) is returned when
EOF
or an error is encountered.
/etc/protocols
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE | ATTRIBUTE VALUE |
---|---|
Interface Stability | Evolving |
These functions use a static data space; if the data is needed for future use, it should be copied before any subsequent calls overwrite it. Only the Internet protocols are currently understood.
The getprotobynumber() function is not yet implemented in ChorusOS 4.0.
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | FILES | ATTRIBUTES | SEE ALSO | BUGS | RESTRICTIONS