df9ebf1eea
GNU readline defines the return value of write_history() as "zero if OK, else an errno code". libedit's version of that function used to have a different definition (to wit, "-1 if error, else the number of lines written to the file"). We tried to work around that by checking whether errno had become nonzero, but this method has never been kosher according to the published API of either library. It's reportedly completely broken in recent Ubuntu releases: psql bleats about "No such file or directory" when saving ~/.psql_history, even though the write worked fine. However, libedit has been following the readline definition since somewhere around 2006, so it seems all right to finally break compatibility with ancient libedit releases and trust that the return value is what readline specifies. (I'm not sure when the various Linux distributions incorporated this fix, but I did find that OS X has been shipping fixed versions since 10.5/Leopard.) If anyone is still using such an ancient libedit, they will find that psql complains it can't write ~/.psql_history at exit, even when the file was written correctly. This is no worse than the behavior we're fixing for current releases. Back-patch to all supported branches.
PostgreSQL Database Management System ===================================== This directory contains the source code distribution of the PostgreSQL database management system. PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings. PostgreSQL has many language interfaces, many of which are listed here: http://www.postgresql.org/download See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at http://www.postgresql.org/download/. For more information look at our web site located at http://www.postgresql.org/.