getprotobyname()
Get a protocol entry, given a name
Synopsis:
#include <netdb.h>
struct protoent * getprotobyname( const char * name );
Arguments:
- name
- The name of the protocol whose entry you want to get.
Library:
libsocket
Use the -l socket option to qcc to link against this library.
Description:
The getprotobyname() function gets the entry for the given name from the protocol database, /etc/protocols. This function returns a pointer to a structure of type protoent , which contains the broken-out fields of a line in the network protocol database.
The setprotoent() function opens and rewinds the file. If you pass a nonzero stayopen argument to setprotoent(), the protocol database isn't closed after each call to getprotobyname() or getprotobynumber() .
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.
Returns:
A pointer to a valid protoent structure, or NULL if an error occurs.
Files:
- /etc/protocols
- Protocol name database file.
Classification:
| Safety: | |
|---|---|
| Cancellation point | Yes |
| Interrupt handler | No |
| Signal handler | No |
| Thread | No |
Caveats:
This function uses static data; if you need the data for future use, copy it before any subsequent calls overwrite it.
Currently, only the Internet protocols are understood.