added safety nets to TMUX_PROGRAM introspection in case readlink or l…

…sof return broken values (2)

.tmux.conf

@@ -139,7 +139,7 @@ bind P choose-buffer    # choose which buffer to paste from
 # -- 8< ------------------------------------------------------------------------
 
 %if #{==:#{TMUX_PROGRAM},}
-  run 'TMUX_PROGRAM="$(LSOF=$(PATH="$PATH:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin" command -v lsof); $LSOF -b -w -a -d txt -p #{pid} -Fn 2>/dev/null | perl -n -e "if (s/^n((?:.(?!dylib$|so$))+)$/\1/g && s/(?:\s+\([^\s]+?\))?$//g) { print; exit } } exit 1; {" || readlink "/proc/#{pid}/exe" 2>/dev/null)"; {[ -f "$TMUX_PROGRAM" ] && [ -x "$TMUX_PROGRAM" ]} || TMUX_PROGRAM="$(command -v tmux || printf tmux)"; "$TMUX_PROGRAM" -S #{socket_path} set-environment -g TMUX_PROGRAM "$TMUX_PROGRAM"'
+  run 'TMUX_PROGRAM="$(LSOF=$(PATH="$PATH:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin" command -v lsof); $LSOF -b -w -a -d txt -p #{pid} -Fn 2>/dev/null | perl -n -e "if (s/^n((?:.(?!dylib$|so$))+)$/\1/g && s/(?:\s+\([^\s]+?\))?$//g) { print; exit } } exit 1; {" || readlink "/proc/#{pid}/exe" 2>/dev/null)"; { [ -f "$TMUX_PROGRAM" ] && [ -x "$TMUX_PROGRAM" ]; } || TMUX_PROGRAM="$(command -v tmux || printf tmux)"; "$TMUX_PROGRAM" -S #{socket_path} set-environment -g TMUX_PROGRAM "$TMUX_PROGRAM"'
 %endif
 %if #{==:#{TMUX_SOCKET},}
   run '"$TMUX_PROGRAM" -S #{socket_path} set-environment -g TMUX_SOCKET "#{socket_path}"'