BLUETOOTH(3)

BLUETOOTH(3) | Library Functions Manual | BLUETOOTH(3)

# NAME

`bt_gethostbyname`, `bt_gethostbyaddr`, `bt_gethostent`, `bt_sethostent`, `bt_endhostent`, `bt_getprotobyname`, `bt_getprotobynumber`, `bt_getprotoent`, `bt_setprotoent`, `bt_endprotoent`, `bt_aton`, `bt_ntoa` —
Bluetooth host lookup routines

# LIBRARY

Bluetooth Library (libbluetooth, -lbluetooth)

# SYNOPSIS

`#include <bluetooth.h>`

struct hostent *
`bt_gethostbyname`(const char *name);

struct hostent *
`bt_gethostbyaddr`(const char *addr, int len, int type);

struct hostent *
`bt_gethostent`(void);

void
`bt_sethostent`(int stayopen);

void
`bt_endhostent`(void);

struct protoent *
`bt_getprotobyname`(const char *name);

struct protoent *
`bt_getprotobynumber`(int proto);

struct protoent *
`bt_getprotoent`(void);

void
`bt_setprotoent`(int stayopen);

void
`bt_endprotoent`(void);

int
`bt_aton`(const char *str, bdaddr_t *ba);

const char *
`bt_ntoa`(const bdaddr_t *ba, char *str);

# DESCRIPTION

The `bt_gethostent`(), `bt_gethostbyname`(), and `bt_gethostbyaddr`() functions each return a pointer to an object with the hostent structure describing a Bluetooth host referenced by name or by address, respectively.

The name argument passed to `bt_gethostbyname`() should point to a `NUL`-terminated hostname. The addr argument passed to `bt_gethostbyaddr`() should point to an address which is len bytes long, in binary form (i.e., not a Bluetooth BD_ADDR in human readable ASCII form). The type argument specifies the address family of this address and must be set to `AF_BLUETOOTH`.

The structure returned contains the information obtained from a line in /etc/bluetooth/hosts file.

The `bt_sethostent`() function controls whether /etc/bluetooth/hosts file should stay open after each call to `bt_gethostbyname`() or `bt_gethostbyaddr`(). If the stayopen flag is non-zero, the file will not be closed.

The `bt_endhostent`() function closes the /etc/bluetooth/hosts file.

The `bt_getprotoent`(), `bt_getprotobyname`(), and `bt_getprotobynumber`() functions each return a pointer to an object with the protoent structure describing a Bluetooth Protocol Service Multiplexer referenced by name or number, respectively.

The name argument passed to `bt_getprotobyname`() should point to a `NUL`-terminated Bluetooth Protocol Service Multiplexer name. The proto argument passed to `bt_getprotobynumber`() should have numeric value of the desired Bluetooth Protocol Service Multiplexer.

The structure returned contains the information obtained from a line in /etc/bluetooth/protocols file.

The `bt_setprotoent`() function controls whether /etc/bluetooth/protocols file should stay open after each call to `bt_getprotobyname`() or `bt_getprotobynumber`(). If the stayopen flag is non-zero, the file will not be closed.

The `bt_endprotoent`() function closes the /etc/bluetooth/protocols file.

The `bt_aton`() routine interprets the specified character string as a Bluetooth address, placing the address into the structure provided. It returns 1 if the string was successfully interpreted, or 0 if the string is invalid.

The routine `bt_ntoa`() takes a Bluetooth address and places an ASCII string representing the address into the buffer provided. It is up to the caller to ensure that provided buffer has enough space. If no buffer was provided then an internal static buffer will be used.

# FILES

/etc/bluetooth/hosts
/etc/bluetooth/protocols

# EXAMPLES

Print out the hostname associated with a specific BD_ADDR:

    const char *bdstr = "00:01:02:03:04:05";
    bdaddr_t bd;
    struct hostent *hp;

    if (!bt_aton(bdstr, &bd))
    	errx(1, "can't parse BD_ADDR %s", bdstr);

    if ((hp = bt_gethostbyaddr((const char *)&bd,
        sizeof(bd), AF_BLUETOOTH)) == NULL)
    	errx(1, "no name associated with %s", bdstr);

    printf("name associated with %s is %s\n", bdstr, hp->h_name);

# RETURN VALUES

Error return status from `bt_gethostent`(), `bt_gethostbyname`(), and `bt_gethostbyaddr`() is indicated by return of a `NULL` pointer. The external integer h_errno may then be checked to see whether this is a temporary failure or an invalid or unknown host. The routine herror(3) can be used to print an error message describing the failure. If its argument string is non-`NULL`, it is printed, followed by a colon and a space. The error message is printed with a trailing newline.

The variable h_errno can have the following values:

`HOST_NOT_FOUND`
  No such host is known.
`NO_RECOVERY`
  Some unexpected server failure was encountered. This is a non-recoverable error.

The `bt_getprotoent`(), `bt_getprotobyname`(), and `bt_getprotobynumber`() return `NULL` on EOF or error.

# SEE ALSO

gethostbyaddr(3), gethostbyname(3), getprotobyname(3), getprotobynumber(3), herror(3), inet_aton(3), inet_ntoa(3)

# HISTORY

`libbluetooth` first appeared in FreeBSD was ported to NetBSD 4.0 and extended by Iain Hibbert for Itronix, Inc.

# AUTHORS

Maksim Yevmenkin <m_evmenkin@yahoo.com>
Iain Hibbert

# CAVEATS

The `bt_gethostent`() function reads the next line of /etc/bluetooth/hosts, opening the file if necessary.

The `bt_sethostent`() function opens and/or rewinds the /etc/bluetooth/hosts file.

The `bt_getprotoent`() function reads the next line of /etc/bluetooth/protocols, opening the file if necessary.

The `bt_setprotoent`() function opens and/or rewinds the /etc/bluetooth/protocols file.

# BUGS

These functions use static data storage; if the data is needed for future use, it should be copied before any subsequent calls overwrite it.

October 25, 2011 | NetBSD 10.0