@kbd{C-x @key{RET} p} in the shell buffer. @xref{Communication
Coding}.
+@cindex @env{INSIDE_EMACS} environment variable
+ Emacs sets the envitonment variable @env{INSIDE_EMACS} to @code{t}
+in the subshell. Programs can check this variable to determine
+whether they are running inside an Emacs subshell.
+
@cindex @env{EMACS} environment variable
- Unless the environment variable @env{EMACS} is already defined,
-Emacs defines it in the subshell, with value equal to Emacs's absolute
-file name. A shell script
-can check this variable to determine whether it has been run from an
-Emacs subshell.
+ Emacs also sets the @env{EMACS} environment variable to @code{t} if
+it is not already defined. @strong{Warning:} This environment
+variable is deprecated. Programs that check this variable should be
+changed to check @env{INSIDE_EMACS} instead.
@node Shell Mode
@subsection Shell Mode