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(emacs)Compilation Mode

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Compilation Mode
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   The `*compilation*' buffer uses a special major mode, Compilation
mode, whose main feature is to provide a convenient way to look at the
source line where the error happened.

   If you set the variable `compilation-scroll-output' to a non-`nil'
value, then the compilation buffer always scrolls to follow output as
it comes in.

`C-x `'
     Visit the locus of the next compiler error message or `grep' match.

`<RET>'
     Visit the locus of the error message that point is on.  This
     command is used in the compilation buffer.

`Mouse-2'
     Visit the locus of the error message that you click on.

   You can visit the source for any particular error message by moving
point in the `*compilation*' buffer to that error message and typing
<RET> (`compile-goto-error').  Alternatively, you can click `Mouse-2'
on the error message; you need not switch to the `*compilation*' buffer
first.

   To parse the compiler error messages sequentially, type `C-x `'
(`next-error').  The character following the `C-x' is the backquote or
"grave accent," not the single-quote.  This command is available in all
buffers, not just in `*compilation*'; it displays the next error
message at the top of one window and source location of the error in
another window.

   The first time `C-x `' is used after the start of a compilation, it
moves to the first error's location.  Subsequent uses of `C-x `'
advance down to subsequent errors.  If you visit a specific error
message with <RET> or `Mouse-2', subsequent `C-x `' commands advance
from there.  When `C-x `' gets to the end of the buffer and finds no
more error messages to visit, it fails and signals an Emacs error.

   `C-u C-x `' starts scanning from the beginning of the compilation
buffer.  This is one way to process the same set of errors again.

   To parse messages from the compiler, Compilation mode uses the
variable `compilation-error-regexp-alist' which lists various formats
of error messages and tells Emacs how to extract the source file and
the line number from the text of a message.  If your compiler isn't
supported, you can tailor Compilation mode to it by adding elements to
that list.  A similar variable `grep-regexp-alist' tells Emacs how to
parse output of a `grep' command.

   Compilation mode also redefines the keys <SPC> and <DEL> to scroll
by screenfuls, and `M-n' and `M-p' to move to the next or previous
error message.  You can also use `M-{' and `M-}' to move up or down to
an error message for a different source file.

   The features of Compilation mode are also available in a minor mode
called Compilation Minor mode.  This lets you parse error messages in
any buffer, not just a normal compilation output buffer.  Type `M-x
compilation-minor-mode' to enable the minor mode.  This defines the keys
<RET> and `Mouse-2', as in the Compilation major mode.

   Compilation minor mode works in any buffer, as long as the contents
are in a format that it understands.  In an Rlogin buffer (Note: Remote
Host), Compilation minor mode automatically accesses remote source
files by FTP (Note: File Names).