MySQL 8.4 C API Developer Guide  /  C API Binary Log Interface  /  Overview of the C API Binary Log Interface

10.1 Overview of the C API Binary Log Interface

The following simple example program demonstrates the binary log C API functions. Program notes:

  • mysql is assumed to be a valid connection handler.

  • The initial SET statement sets the @source_binlog_checksum user-defined variable that the server takes as an indication that the client is checksum-aware. This client does nothing with checksums, but without this statement, a server that includes checksums in binary log events will return an error for the first attempt to read an event containing a checksum. The value assigned to the variable is immaterial; what matters is that the variable exist.

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if (mysql_query(mysql, "SET @source_binlog_checksum='ALL'")) { fprintf(stderr, "mysql_query() failed\n"); fprintf(stderr, "Error %u: %s\n", mysql_errno(mysql), mysql_error(mysql)); exit(1); } MYSQL_RPL rpl; rpl.file_name_length = 0; rpl.file_name = NULL; rpl.start_position = 4; rpl.server_id = 0; rpl.flags = 0; if (mysql_binlog_open(mysql, &rpl)) { fprintf(stderr, "mysql_binlog_open() failed\n"); fprintf(stderr, "Error %u: %s\n", mysql_errno(mysql), mysql_error(mysql)); exit(1); } for (;;) /* read events until error or EOF */ { if (mysql_binlog_fetch(mysql, &rpl)) { fprintf(stderr, "mysql_binlog_fetch() failed\n"); fprintf(stderr, "Error %u: %s\n", mysql_errno(mysql), mysql_error(mysql)); break; } if (rpl.size == 0) /* EOF */ { fprintf(stderr, "EOF event received\n"); break; } fprintf(stderr, "Event received of size %lu.\n", rpl.size); } mysql_binlog_close(mysql, &rpl);

For additional examples that show how to use these functions, look in a MySQL source distribution for these source files:

  • mysqlbinlog.cc in the client directory

  • mysql_client_test.c in the testclients directory