</para>

<para>

This parameter can only be set in the <filename>postgresql.conf</filename>

file or on the server command line. It isignored unless

file or on the server command line. It isonly used if

<varname>archive_mode</varname> was enabled at server start and

<varname>archive_library</varname> is set to an empty string.

<varname>archive_library</varname> is set to an empty string. If both

<varname>archive_command</varname> and <varname>archive_library</varname>

are set, an error will be raised.

If <varname>archive_command</varname> is an empty string (the default) while

<varname>archive_mode</varname> is enabled (and <varname>archive_library</varname>

is set to an empty string), WAL archiving is temporarily

<para>

The library to use for archiving completed WAL file segments. If set to

an empty string (the default), archiving via shell is enabled, and

<xref linkend="guc-archive-command"/> is used. Otherwise, the specified

<xref linkend="guc-archive-command"/> is used. If both

<varname>archive_command</varname> and <varname>archive_library</varname>

are set, an error will be raised. Otherwise, the specified

shared library is used for archiving. The WAL archiver process is

restarted by the postmaster when this parameter changes. For more

information, see <xref linkend="backup-archiving-wal"/> and

ConfigReloadPending= false;

ProcessConfigFile(PGC_SIGHUP);

if (XLogArchiveLibrary[0]!='\0'&&XLogArchiveCommand[0]!='\0')

ereport(ERROR,

(errcode(ERRCODE_INVALID_PARAMETER_VALUE),

errmsg("both archive_command and archive_library set"),

errdetail("Only one of archive_command, archive_library may be set.")));

archiveLibChanged=strcmp(XLogArchiveLibrary,archiveLib)!=0;

pfree(archiveLib);

{

ArchiveModuleInitarchive_init;

if (XLogArchiveLibrary[0]!='\0'&&XLogArchiveCommand[0]!='\0')

ereport(ERROR,

(errcode(ERRCODE_INVALID_PARAMETER_VALUE),

errmsg("both archive_command and archive_library set"),

errdetail("Only one of archive_command, archive_library may be set.")));

memset(&ArchiveContext,0,sizeof(ArchiveModuleCallbacks));