Looking at the last few published versions, release and prerelease, I see that lines are bounded in shell.c as is normal for *Nix systems, with a single ASCII linefeed character. (or \\n in your parlance) Looking at the shell.c produced on my Windows machine using the Fossil repository for SQLite, I see that its lines are bounded by a CR LF sequence (\\r\\n) as is normal on the platform. This makes me wonder what strange combination of repository movement and build platform has led to your strange line bounds. Perhaps you should say, just in case this is actually a fixable problem rather than something quirky and unlikely to repeat under normal conditions. [Added via later edit: ] Because, obviously, you are causing shell.c to be built, I think it behooves you, as a developer considerate of those who might deal with this issue, to: State what platform you are using to build shell.c and the amalgamation; State what platform the source repository was copied from if not created on the build platform; State what version and build of TCL you are using; and what, if any, editing you have done to the various sources that are combined to form shell.c I suggest also that you see whether your problem is restricted to just portions of your shell.c, arising from use of your own editor, or have somehow affected all line endings in shell.c . I think that, until these issues are resolved, it is quite premature to put the word "BUG" in the thread title. If I had done that, I would remove it via the forum's edit feature.