nut/man/upsclient.3

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2010-03-25 23:20:59 +00:00
.TH UPSCLIENT 3 "Mon Jan 22 2007" "" "Network UPS Tools (NUT)"
.SH NAME
upsclient \- Network UPS Tools client access library
.SH SYNOPSIS
.SH DESCRIPTION
The Network UPS Tools (NUT) \fBupsclient\fP library provides a number of
useful functions for programs to use when communicating with
\fBupsd\fP(8). Many of the low\(hylevel socket and protocol details are
handled automatically when using this interface.
.PP
State is maintained across calls in an opaque structure called UPSCONN.
Callers are expected to create one per connection. These will be
provided to most of the \fBupsclient\fP functions. The format of this
structure is subject to change, and client programs must not reference
elements within it directly.
.PP
.SH NETWORK FUNCTIONS
To create a new connection, use \fBupscli_connect\fP(3). This will also
initialize the UPSCONN structure. To verify that a connection has been
established later, \fBupscli_fd\fP(3) can be used to return the
file descriptor. Clients wishing to check for the presence and
operation of SSL on a connection may call \fBupscli_ssl\fR(3).
.PP
The majority of clients will use \fBupscli_get\fP(3) to retrieve single
items from the server. To retrieve a list, use
\fBupscli_list_start\fP(3) to get it started, then call
\fBupscli_list_next\fP(3) for each element.
.PP
Raw lines of text may be sent to \fBupsd\fP with
\fBupscli_sendline\fP(3). Reading raw lines is possible with
\fBupscli_readline\fP(3). Client programs are expected to format these
lines according to the protocol, as no checking will be performed before
transmission.
.PP
At the end of a connection, you must call \fBupsclient_disconnect\fR(3)
to disconnect from \fBupsd\fP and release any dynamic memory associated
with the UPSCONN structure. Failure to call this function will result
in memory and file descriptor leaks in your program.
.PP
.SH ERROR HANDLING
In the event of an error, \fBupscli_strerror\fR(3) will provide
human\(hyreadable details on what happened. \fBupscli_upserror\fR(3) may
also be used to retrieve the error number. These numbers are defined in
\fBupsclient.h\fP as \fIUPSCLI_ERR_*\fP.
.PP
.SH "SEE ALSO"
.BR upscli_connect "(3), "upscli_disconnect "(3), "upscli_fd "(3), "
.BR upscli_getvar "(3), "upscli_list_next "(3), "
.BR upscli_list_start "(3), "upscli_readline "(3), "
.BR upscli_sendline "(3), "
.BR upscli_splitaddr "(3), "upscli_splitname "(3), "
.BR upscli_ssl "(3), "upscli_strerror "(3), "
.BR upscli_upserror "(3) "