XCOMM!SHELL_CMD
XCOMM

XCOMM redirect errors to a file in user's home directory if we can

errfile="$HOME/.xsession-errors"
if ( umask 077 && cp /dev/null "$errfile" 2> /dev/null )
then
	exec > "$errfile" 2>&1
else
    mktemp="MKTEMP_COMMAND"
    if [ "x$mktemp" != "x" -a -x "$mktemp" ]
    then
	for errfile in "${TMPDIR-/tmp}/xses-$USER" "/tmp/xses-$USER"
	do
		if ef="$( umask 077 && $mktemp "$errfile.XXXXXX" 2> /dev/null)"
		then
			exec > "$ef" 2>&1
			mv "$ef" "$errfile" 2> /dev/null
			break
		fi
	done
    else
XCOMM Since this system doesn't have a mktemp command to allow secure
XCOMM creation of files in shared directories, no fallback error log
XCOMM is being used.   See https://bugs.freedesktop.org/show_bug.cgi?id=5898
XCOMM
XCOMM 	for errfile in "${TMPDIR-/tmp}/xses-$USER" "/tmp/xses-$USER"
XCOMM	do
XCOMM		if ( umask 077 && cp /dev/null "$errfile" 2> /dev/null )
XCOMM		then
XCOMM			exec > "$errfile" 2>&1
XCOMM			break
XCOMM		fi
XCOMM	done

	exec > /dev/null 2>&1
    fi
fi

case $# in
1)
	case $1 in
	failsafe)
		exec BINDIR/xterm -geometry 80x24-0-0
		;;
	esac
esac

XCOMM The startup script is not intended to have arguments.

startup=$HOME/.xsession
resources=$HOME/.Xresources

if [ -s "$startup" ]; then
	if [ -x "$startup" ]; then
		exec "$startup"
	else
		exec /bin/sh "$startup"
	fi
else
	if [ -r "$resources" ]; then
		BINDIR/xrdb -load "$resources"
	fi
	exec BINDIR/xsm
fi