These environment variables are used to initialize the variable
@code{temporary-file-directory}, which specifies a directory in which
to put temporary files (@pxref{Backup}). Emacs tries to use
@env{TMPDIR} first. If that is unset, Emacs normally falls back on
@file{/tmp}, but on MS-Windows and MS-DOS it instead falls back on
@env{TMP}, then @env{TEMP}, and finally @file{c:/temp}.
These environment variables are used to initialize the variable
@code{temporary-file-directory}, which specifies a directory in which
to put temporary files (@pxref{Backup}). Emacs tries to use
@env{TMPDIR} first. If that is unset, Emacs normally falls back on
@file{/tmp}, but on MS-Windows and MS-DOS it instead falls back on
@env{TMP}, then @env{TEMP}, and finally @file{c:/temp}.