As said in the comments above, you won't be able to change that on a large scale basis. Applications calling Terminal.app will do that by calling its Bundle identifier, com.apple.terminal. You'd have to change this to "fake" the Terminal and redirect to another one. Is that's possible? I highly doubt so.
This means that every application calling Terminal will have a setting for the bundle identifier used. Some will probably have that hardcoded, others should allow changing it, either through Preferences or through a preference list setting.
How to make BBEdit use another Terminal
For BBEdit, that's relatively easy according to the release notes. This is for version 8.7 though, and I can't find it in the "Experts Preferences" of version 10 anymore. Maybe they've removed the feature.
defaults write com.barebones.bbedit Misc:TerminalBundleIDOverride "com.googlecode.iTerm2"
Just replace com.apple.Terminal with the bundle identified of the other terminal emulator, e.g. com.googlecode.iterm2 for iTerm2.
A similar entry can be found on secrets.blacktree.com, although it doesn't appear to be working (I've never seen a -bundleid datatype in defaults).
The best idea would be to bring up a support request with BBEdit's developers.
How to make Alfred use another Terminal
Alfred's shell extensions use the terminal emulator you specify, according to the help.
You can select to use the OS X Terminal.app or iTerm, as well as your prefix for Shell commands in the Alfred preferences.
It didn't work for me at first, so I had to delete iTerm.app, delete Alfred and its preferences/caches, then reinstall iTerm2. This is explained in the Alfred support forums.
1Which app wants to open Terminal.app? – slhck – 2011-08-05T20:24:19.987
When something runs
tell application "Terminal"in applescript, when something runsopen -a Terminal,open -a /Applications/Utilities/Terminal.app,/Applications/Utilities/Terminal.app/Contents/MacOS/Terminaloropen -b com.apple.terminaletc etc... – Tyilo – 2011-08-05T20:28:58.110May I ask why? You cover probably all cases I could think of, but in order to do that, you'd need to effectively "turn" Terminal.app into iTerm.app, either by changing the
– slhck – 2011-08-05T21:03:21.483Info.plistfile located within Terminal.app (read more about that here). Or just move theTerminalexecutable away and replace it with iTerm's executable. Don't know if that will work as expected though.Because I normally use iTerm2 and never Terminal, only when another program oens it. – Tyilo – 2011-08-05T21:12:03.423
2To be honest, I've never seen any program opening a Terminal so far. Everything you mentioned above involves manually opening, so it shouldn't be hard to change these lines to iTerm2 (which is different from iTerm, by the way). Can you be a bit more specific, maybe? I still don't know which use case you are talking about. – slhck – 2011-08-05T21:15:58.570
1@slhck I surely hope that Apple would prevent (by checksums, codesigning and sandboxing) replacing Terminal´s executables with other code! And I totally agree, I´ve never seen other .apps open Terminal; only .command files could be an issue, but you can change the "open with…" assignment there. – Asmus – 2011-08-06T11:37:55.610
@Asmus & slhck I'm using some applications that does this, BBEdit and Alfred are the only one's I can think of right now – Tyilo – 2011-08-06T12:15:52.940
Maybe we should investigate those specific issues then -- can you clarify your post a bit? (What you're doing in Alfred/BBEdit)
– slhck – 2011-08-06T13:14:04.503