diff -uNr k2pdfopt_v2.51/willuslib/linux.c k2pdfopt_v2.51.mod/willuslib/linux.c
--- k2pdfopt_v2.51/willuslib/linux.c	2018-12-07 06:04:19.000000000 +0200
+++ k2pdfopt_v2.51.mod/willuslib/linux.c	2020-01-01 22:57:54.060671849 +0200
@@ -51,14 +51,8 @@
     static char file[4096];
     int   index,j;
     int used[16];
-    static char *stddirs[] = {"/usr/sbin",
-                              "/sbin",
-                              "/bin",
-                              "/usr/bin",
-                              "/usr/local/bin",
-                              "/usr/kerberos/sbin",
-                              "/usr/kerberos/bin",
-                              "/usr/X11R6/bin",
+    static char *stddirs[] = {"@TERMUX_PREFIX@/bin",
+                              "@TERMUX_PREFIX@/bin/applets",
                               ".",
                               ""};
 
diff -uNr k2pdfopt_v2.51/willuslib/wfile.c k2pdfopt_v2.51.mod/willuslib/wfile.c
--- k2pdfopt_v2.51/willuslib/wfile.c	2018-07-27 20:47:22.000000000 +0300
+++ k2pdfopt_v2.51.mod/willuslib/wfile.c	2020-01-01 22:59:22.030332744 +0200
@@ -2003,7 +2003,7 @@
             strcpy(dir,".");
         }
 #else
-    strcpy(dir,"/tmp");
+    strcpy(dir,"@TERMUX_PREFIX@/tmp");
 #endif
     }
 
diff -uNr k2pdfopt_v2.51/willuslib/wgs.c k2pdfopt_v2.51.mod/willuslib/wgs.c
--- k2pdfopt_v2.51/willuslib/wgs.c	2018-12-30 19:31:32.000000000 +0200
+++ k2pdfopt_v2.51.mod/willuslib/wgs.c	2020-01-01 22:58:58.573156564 +0200
@@ -223,8 +223,7 @@
                             "+\\gs","+\\ghostgum","\\gs*","\\ghostgum*",""};
 #else
     static char *gsnames[]={"gs",""};
-    static char *folders[]={"/usr/bin","/usr/share/gs","/usr/local/gs","/opt/gs",
-                            "/usr/share/gs*","/usr/local/gs*","/opt/gs*",""};
+    static char *folders[]={"@TERMUX_PREFIX@/bin",""};
 #endif