mirror/postgresql
2
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2024-12-15 08:20:16 +08:00
Code Issues Packages Projects Releases Wiki Activity

docs: update libpq's PQputCopyData and PQputCopyEnd

Browse Source 
Clarify the meaning of libpq return values for PQputCopyData and
PQputCopyEnd, particularly in non-blocking mode.

Report by Robert Haas
This commit is contained in:
Bruce Momjian 2015-01-22 13:30:08 -05:00
parent d060e07fa9
commit b04d691613
1 changed files with 17 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
doc/src/sgml/libpq.sgml
View File

@ -4318,8 +4318,8 @@ int PQsetnonblocking(PGconn *conn, int arg);
<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>
@ -4961,9 +4961,9 @@ int PQputCopyData(PGconn *conn,
<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 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.
The result is 1 if the data was queued, zero if it was not queued
because of full buffers (this will only happen 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.)
@ -5009,13 +5009,18 @@ int PQputCopyEnd(PGconn *conn,
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>