getprotobynumber(3POSIX)

NAME | SYNOPSIS | API RESTRICTIONS | DESCRIPTION | RETURN VALUES | FILES | ATTRIBUTES | SEE ALSO | BUGS | RESTRICTIONS

NAME

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

SYNOPSIS

$(OS_DIR)/lib/libc.a
#include <netdb.h>

struct protoent * getprotoent(void);
struct protoent * getprotobyname(char * name);
structprotoent *getprotobynumber(int proto);
void setprotoent(int stayopen);
void endprotoent(void);

API RESTRICTIONS

The function or functions documented here may not be used safely in all application contexts with all APIs provided in the ChorusOS 5.0 product.

See API(5FEA) for details.

DESCRIPTION

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:

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.

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).

RETURN VALUES

A NULL pointer ( 0 ) is returned when EOF or an error is encountered.

FILES

/etc/protocols

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Interface Stability	Evolving

SEE ALSO

protocols(4CC)

BUGS

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.

RESTRICTIONS

The getprotobynumber() function is not yet implemented in ChorusOS 5.0.

ChorusOS 5.0  Last Revised December 2001

NAME | SYNOPSIS | API RESTRICTIONS | DESCRIPTION | RETURN VALUES | FILES | ATTRIBUTES | SEE ALSO | BUGS | RESTRICTIONS