diff -u -r ../fish-3.0.1/src/env.cpp ./src/env.cpp
--- ../fish-3.0.1/src/env.cpp	2019-02-11 12:13:15.000000000 +0000
+++ ./src/env.cpp	2019-02-13 22:19:56.975817836 +0000
@@ -1663,7 +1663,7 @@
         auto pwuid = getpwuid(geteuid());
         const char *uname = pwuid ? pwuid->pw_name : NULL;
         // /tmp/fish.user
-        std::string tmpdir = "/tmp/fish.";
+        std::string tmpdir = "@TERMUX_PREFIX@/tmp/fish.";
         if (uname) {
             tmpdir.append(uname);
         }