For using a shell commands through a terminal program, where can I find documentation or help or man pages for the commands as implemented in Android?
While it would be nice to have them on the device via man, PDF or web-based would be fine, too.
When I run "man" from terminal, I get an error and I haven't found a good source online.
You may have a look at http://www.busybox.net/downloads/BusyBox.html for a description of busybox and the commands provided by it. And trust me, if you are going to do work in the console, you probably want to use busybox.
Most of the terminal commands in android are the limited version of standard Linux/Unix/POSIX terminal commands, provided by the toolbox program. Notably absent from toolbox is the cp (file copy) command, you must use cat file1 > file2 instead. If you spend a lot of time in the shell, you may want to install busybox, which provides a richer set of standard POSIX commands.
There some bit about android shell here: http://benno.id.au/blog/2007/11/13/android-under-the-hood
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