NAME

getprotoent, getprotobynumber, getprotobyname, setprotoent, endprotoent − get protocol entry

SYNOPSIS

#include <netdb.h>

struct protoent ∗getprotoent()

struct protoent ∗getprotobyname(name)
char ∗name;

struct protoent ∗getprotobynumber(proto)
int proto;

setprotoent(stayopen)
int stayopen

endprotoent()

DESCRIPTION

getprotoent, getprotobyname, and getprotobynumber each return a pointer to an object with the following structure containing the broken-out fields of a line in the network protocol data base, /etc/protocols. 

structprotoent {
char∗p_name;/∗ official name of protocol ∗/
char∗∗p_aliases;/∗ alias list ∗/
longp_proto;/∗ protocol number ∗/
};

The members of this structure are:

p_name The official name of the protocol. 

p_aliases A zero terminated list of alternate names for the protocol. 

p_proto The protocol number. 

CX supports both a proprietary version and an 88open Object Compatibility Standard Networking Supplement (OCSNS) version of getprotobyname and getprotobynumber.  The OCSNS versions of these functions check for the existence of the function /etc/bcs_cat and if it exists and has proper execute permission, will issue a popen(3S) call of the command /etc/bcs_cat protocols.  If the file does not exist, the functions will access the /etc/protocols file. 

getprotoent reads the next line of the file /etc/protocols, opening the file if necessary and returning a pointer to protoent structure containing the file entry. 

Setprotoent opens and rewinds the file /etc/protocols.  If the stayopen flag is non-zero, the net data base will not be closed after each call to getprotoent, getprotobyname, or getprotobynumber. 

Endprotoent closes the file /etc/protocols and clears the stayopen flag. 

The functions getprotoent, setprotoent, and endprotoent are defined in the 88open OCSNS.  Their functionality is the same as described above. 

Both versions of getprotobyname and getprotobynumber sequentially search from the beginning of the file until a matching protocol name or protocol number is found, or until EOF is encountered. 

NOTE

The OCSNS versions of the above files may be accessed through special OCS options passed to cc(1) and/or ld(1). 

FILES

/etc/protocols

SEE ALSO

bcs_cat(1), protocols(4C)

DIAGNOSTICS

Null pointer (0) returned on EOF or error. 

BUGS

All information is contained in a static area so it must be copied if it is to be saved.  Only the Internet protocols are currently understood. 

CX/UX Networking