Gets protocol entry from the /etc/protocols file.
Standard C Library (libc.a)
#include <netdb.h> int getprotoent_r(protoent, proto_data) struct protoent *protoent; struct protoent_data *proto_data;
The getprotoent_r subroutine retrieves protocol information from the /etc/protocols file. An application program can use the getprotoent_r subroutine to access a protocol name, its aliases, and protocol number. The getprotoent_r subroutine opens and performs a sequential read of the /etc/protocols file. This subroutine writes to the protoent structure, which contains the fields for a line of information in the /etc/protocols file.
The netdb.h file defines the protoent structure.
Use the endprotoent_r subroutine to close the /etc/protocols file. Static data is overwritten in subsequent calls when using the getprotoent subroutine. The getprotoent_r subroutine does not overwrite.
| protoent | Points to the protoent structure. |
| proto_data | Points to the proto_data structure. |
The function returns a 0 if successful and a -1 if unsuccessful.
| /etc/protocols | Contains protocol information. |
endprotoent_r Subroutine, setprotoent_r Subroutine, getprotobyname_r Subroutine, getprotobynumber_r Subroutine, and setprotoent_r Subroutine.