UPSCLI_LIST_START(3) NUT Manual UPSCLI_LIST_START(3)NAMEupscli_list_start - begin multi-item retrieval from a UPS
SYNOPSIS
#include <upsclient.h>
int upscli_list_start(UPSCONN_t *ups, int numq, const char **query)
DESCRIPTION
The upscli_list_start() function takes the pointer ups to a UPSCONN_t
state structure, and the pointer query to an array of numq query
elements. It builds a properly-formatted request from those elements
and transmits it to upsd(8).
Upon success, the caller must call upscli_list_next(3) to retrieve the
elements of the list. Failure to retrieve the list will most likely
result in the client getting out of sync with the server due to
buffered data.
USES
This function implements the "LIST" command in the protocol. As a
result, you can use it to request many different things from the
server. Some examples are:
· LIST UPS
· LIST VAR <ups>
· LIST RW <ups>
· LIST CMD <ups>
· LIST ENUM <ups> <var>
· LIST RANGE <ups> <var>
QUERY FORMATTING
To see the list of variables on a UPS called su700, the protocol
command would be LIST VAR su700. To start that list with this function,
you would populate query and numq as follows:
int numq;
const char *query[2];
query[0] = "VAR";
query[1] = "su700";
numq = 2;
All escaping of special characters and quoting of elements with spaces
are handled for you inside this function.
ERROR CHECKING
This function checks the response from upsd(8) against your query. If
it is not starting a list, or is starting the wrong type of list, it
will return an error code.
When this happens, upscli_upserror(3) will return UPSCLI_ERR_PROTOCOL.
RETURN VALUE
The upscli_list_start() function returns 0 on success, or -1 if an
error occurs.
SEE ALSOupscli_fd(3), upscli_get(3), upscli_readline(3), upscli_sendline(3),
upscli_ssl(3), upscli_strerror(3), upscli_upserror(3)Network UPS Tools 08/08/2012 UPSCLI_LIST_START(3)
