Dealing with a basic command-line prompt in a loop can be painful, so many programs, such as shells, interactive programming languages and debuggers, provide a more featureful prompt. For example, pressing the up and down arrows in a good prompt will flip through previously entered input lines. Programs will often make use of the GNU readline library for this functionality.

If you need to use a program that only has a basic prompt, you may be able to wrap it with the program rlwrap to get some more advanced features. From the man page:

rlwrap runs the specified command, intercepting user input in order to provide readline's line editing, persistent history and completion.

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There are many options to add (programmable) completion, handle multi-line input, colour and re-write prompts. If you don't need them (and you probably don't), you can skip the rest of this manpage.

For example, I recently used rlwrap with jdb, the Java debugger, and Ikarus, a Scheme compiler.

The first release of Lua 5.2 is now ready.

Universal feed parser, handles RSS 0.9x, RSS 1.0, RSS 2.0, CDF, Atom 0.3, and Atom 1.0 feeds

We have entered the final release-candidate cycle for Lua 5.2.0.

Most people seem to have an opinion as to whether exceptions in C++ are slow or fast, but very few people have put any useful numbers out there. Here's a lower bound.

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Users can now view plotted data as column charts, and add U.S. recession shading, while using the "View chart" function of the Data Download Program (DDP).

Users can now view plotted data as column charts, and add U.S. recession shading, while using the "View chart" function of the Data Download Program (DDP).

Roberto Ierusalimschy, the chief architect of Lua, will be visiting Stanford University for three months on a Tinker Professorship starting in January 2012.

October 4, 2011 Correction to H.10 and G.5 released October 3, 2011 The data for the H.10 exchange rates did not include data for September 28. Subsequently, the calculation of the G.5 rates were affected because of the missing data. Updated data for H.10 and G.5 are now available. http://www.federalreserve.gov/releases/h10/current/http://www.federalreserve.gov/releases/g5/current/

The H.10 Real Monthly Indexes published on September 1 did not include the August 2011 data. Updated data for August Real Monthly Indexes are now available. http://www.federalreserve.gov/releases/h10/summary/default.htm