<para>

In the nonblocking state, calls to

<function>PQsendQuery</function>, <function>PQputline</function>,

<function>PQputnbytes</function>,and

<function>PQendcopy</function> will not block but instead return

<function>PQputnbytes</function>,<function>PQputCopyData</function>,

and<function>PQendcopy</function> will not block but instead return

an error if they need to be called again.

</para>

<para>

Transmits the <command>COPY</command> data in the specified

<parameter>buffer</>, of length <parameter>nbytes</>, to the server.

The result is 1 if the data wassent, zero if it was notsent

becausethe attempt would block(thiscase isonlypossible if the

connection is in nonblocking mode),or -1 if an error occurred.

The result is 1 if the data wasqueued, zero if it was notqueued

becauseof full buffers(thiswillonlyhappen in nonblocking mode),

or -1 if an error occurred.

(Use <function>PQerrorMessage</function> to retrieve details if

the return value is -1. If the value is zero, wait for write-ready

and try again.)

connections.)

</para>

<para>

The result is 1 if the termination data was sent, zero if it was

not sent because the attempt would block (this case is only possible

if the connection is in nonblocking mode), or -1 if an error

occurred. (Use <function>PQerrorMessage</function> to retrieve

details if the return value is -1. If the value is zero, wait for

write-ready and try again.)

<para>

The result is 1 if the termination message was sent; or in

nonblocking mode, this may only indicate that the termination

message was successfully queued. (In nonblocking mode, to be

certain that the data has been sent, you should next wait for

write-ready and call <function>PQflush</>, repeating until it

returns zero.) Zero indicates that the function could not queue

the termination message because of full buffers; this will only

happen in nonblocking mode. (In this case, wait for

write-ready and try the <function>PQputCopyEnd</> call

again.) If a hard error occurs, -1 is returned; you can use

<function>PQerrorMessage</function> to retrieve details.

</para>

<para>