web2c: Editor invocation
4.4 Editor invocation
=====================
TeX, Metafont, and MetaPost all (by default) stop and ask for user
intervention at an error. If the input came from a file, and the user
responds with 'e' or 'E', the program invokes an editor.
Specifying '--with-editor=CMD' to 'configure' sets the default editor
command string to CMD. The environment variables/configuration values
'TEXEDIT', 'MFEDIT', and 'MPEDIT' (respectively) override this. If
'--with-editor' is not specified, the default is 'vi +%d %s' on Unix,
and an invocation of the TeXworks editor on Windows. (See 'texmf.cnf'
for the precise values.)
In this string, '%d' is replaced by the line number of the error, and
'%s' is replaced by the name of the current input file.