CK Sin
Ethernetwebsoc
Dependencies: C12832_lcd LM75B WebSocketClient mbed-rtos mbed Socket lwip-eth lwip-sys lwip
API functions for name resolving. More...
Go to the source code of this file.
Functions | |
| struct hostent * | lwip_gethostbyname (const char *name) |
| Returns an entry containing addresses of address family AF_INET for the host with name name. | |
| int | lwip_gethostbyname_r (const char *name, struct hostent *ret, char *buf, size_t buflen, struct hostent **result, int *h_errnop) |
| Thread-safe variant of lwip_gethostbyname: instead of using a static buffer, this function takes buffer and errno pointers as arguments and uses these for the result. | |
| void | lwip_freeaddrinfo (struct addrinfo *ai) |
| Frees one or more addrinfo structures returned by getaddrinfo(), along with any additional storage associated with those structures. | |
| int | lwip_getaddrinfo (const char *nodename, const char *servname, const struct addrinfo *hints, struct addrinfo **res) |
| Translates the name of a service location (for example, a host name) and/or a service name and returns a set of socket addresses and associated information to be used in creating a socket with which to address the specified service. | |
Variables | |
| int | h_errno |
| h_errno is exported in netdb.h for access by applications. | |
Detailed Description
API functions for name resolving.
Definition in file netdb.c.
Function Documentation
| void lwip_freeaddrinfo | ( | struct addrinfo * | ai ) |
Frees one or more addrinfo structures returned by getaddrinfo(), along with any additional storage associated with those structures.
If the ai_next field of the structure is not null, the entire list of structures is freed.
- Parameters:
-
ai struct addrinfo to free
| int lwip_getaddrinfo | ( | const char * | nodename, |
| const char * | servname, | ||
| const struct addrinfo * | hints, | ||
| struct addrinfo ** | res | ||
| ) |
Translates the name of a service location (for example, a host name) and/or a service name and returns a set of socket addresses and associated information to be used in creating a socket with which to address the specified service.
Memory for the result is allocated internally and must be freed by calling lwip_freeaddrinfo()!
Due to a limitation in dns_gethostbyname, only the first address of a host is returned. Also, service names are not supported (only port numbers)!
- Parameters:
-
nodename descriptive name or address string of the host (may be NULL -> local address) servname port number as string of NULL hints structure containing input values that set socktype and protocol res pointer to a pointer where to store the result (set to NULL on failure)
- Returns:
- 0 on success, non-zero on failure
| struct hostent* lwip_gethostbyname | ( | const char * | name ) | [read] |
Returns an entry containing addresses of address family AF_INET for the host with name name.
Due to dns_gethostbyname limitations, only one address is returned.
- Parameters:
-
name the hostname to resolve
- Returns:
- an entry containing addresses of address family AF_INET for the host with name name
| int lwip_gethostbyname_r | ( | const char * | name, |
| struct hostent * | ret, | ||
| char * | buf, | ||
| size_t | buflen, | ||
| struct hostent ** | result, | ||
| int * | h_errnop | ||
| ) |
Thread-safe variant of lwip_gethostbyname: instead of using a static buffer, this function takes buffer and errno pointers as arguments and uses these for the result.
- Parameters:
-
name the hostname to resolve ret pre-allocated struct where to store the result buf pre-allocated buffer where to store additional data buflen the size of buf result pointer to a hostent pointer that is set to ret on success and set to zero on error h_errnop pointer to an int where to store errors (instead of modifying the global h_errno)
- Returns:
- 0 on success, non-zero on error, additional error information is stored in *h_errnop instead of h_errno to be thread-safe
Variable Documentation
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