diff --git a/t/30mouse.c b/t/30mouse.c
--- a/t/30mouse.c
+++ b/t/30mouse.c
@@ -14,7 +14,7 @@ int main(int argc, char *argv[])

   tk = termkey_new_abstract("vt100", 0);

-  termkey_push_bytes(tk, "\e[M !!", 6);
+  termkey_push_bytes(tk, "\x1b[M !!", 6);
 
   key.type = -1;
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for mouse press");
@@ -38,7 +38,7 @@ int main(int argc, char *argv[])
   is_int(len, 21, "string length for press");
   is_str(buffer, "MousePress(1) @ (1,1)", "string buffer for press");
 
-  termkey_push_bytes(tk, "\e[M@\"!", 6);
+  termkey_push_bytes(tk, "\x1b[M@\"!", 6);
 
   key.type = -1;
   ev = -1; button = -1; line = -1; col = -1;
@@ -51,7 +51,7 @@ int main(int argc, char *argv[])
   is_int(col,    2,                   "mouse column for drag");
   is_int(key.modifiers, 0,            "modifiers for press");
 
-  termkey_push_bytes(tk, "\e[M##!", 6);
+  termkey_push_bytes(tk, "\x1b[M##!", 6);
 
   key.type = -1;
   ev = -1; button = -1; line = -1; col = -1;
@@ -63,7 +63,7 @@ int main(int argc, char *argv[])
   is_int(col,    3,                     "mouse column for release");
   is_int(key.modifiers, 0,            "modifiers for press");
 
-  termkey_push_bytes(tk, "\e[M0++", 6);
+  termkey_push_bytes(tk, "\x1b[M0++", 6);
 
   key.type = -1;
   ev = -1; button = -1; line = -1; col = -1;
@@ -81,7 +81,7 @@ int main(int argc, char *argv[])
   is_str(buffer, "C-MousePress(1)", "string buffer for Ctrl-press");
 
   // rxvt protocol
-  termkey_push_bytes(tk, "\e[0;20;20M", 10);
+  termkey_push_bytes(tk, "\x1b[0;20;20M", 10);
 
   key.type = -1;
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for mouse press rxvt protocol");
@@ -96,7 +96,7 @@ int main(int argc, char *argv[])
   is_int(col,    20,                  "mouse column for press rxvt protocol");
   is_int(key.modifiers, 0,            "modifiers for press rxvt protocol");
 
-  termkey_push_bytes(tk, "\e[3;20;20M", 10);
+  termkey_push_bytes(tk, "\x1b[3;20;20M", 10);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for mouse release rxvt protocol");
 
@@ -111,7 +111,7 @@ int main(int argc, char *argv[])
   is_int(key.modifiers, 0,            "modifiers for release rxvt protocol");
 
   // SGR protocol
-  termkey_push_bytes(tk, "\e[<0;30;30M", 11);
+  termkey_push_bytes(tk, "\x1b[<0;30;30M", 11);
 
   key.type = -1;
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for mouse press SGR encoding");
@@ -127,7 +127,7 @@ int main(int argc, char *argv[])
   is_int(col,    30,                  "mouse column for press SGR");
   is_int(key.modifiers, 0,            "modifiers for press SGR");
 
-  termkey_push_bytes(tk, "\e[<0;30;30m", 11);
+  termkey_push_bytes(tk, "\x1b[<0;30;30m", 11);
 
   key.type = -1;
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for mouse release SGR encoding");
@@ -139,7 +139,7 @@ int main(int argc, char *argv[])
 
   is_int(ev,     TERMKEY_MOUSE_RELEASE, "mouse event for release SGR");
 
-  termkey_push_bytes(tk, "\e[<0;500;300M", 13);
+  termkey_push_bytes(tk, "\x1b[<0;500;300M", 13);
 
   key.type = -1;
   ev = -1; button = -1; line = -1; col = -1;
diff --git a/t/31position.c b/t/31position.c
index 1748211..86ad1bc 100644
--- a/t/31position.c
+++ b/t/31position.c
@@ -11,7 +11,7 @@ int main(int argc, char *argv[])
 
   tk = termkey_new_abstract("vt100", 0);
 
-  termkey_push_bytes(tk, "\e[?15;7R", 8);
+  termkey_push_bytes(tk, "\x1b[?15;7R", 8);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for position report");
 
@@ -25,7 +25,7 @@ int main(int argc, char *argv[])
   /* A plain CSI R is likely to be <F3> though.
    * This is tricky :/
    */
-  termkey_push_bytes(tk, "\e[R", 3);
+  termkey_push_bytes(tk, "\x1b[R", 3);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for <F3>");
 
diff --git a/t/32modereport.c b/t/32modereport.c
index 31de400..5e49705 100644
--- a/t/32modereport.c
+++ b/t/32modereport.c
@@ -11,7 +11,7 @@ int main(int argc, char *argv[])
 
   tk = termkey_new_abstract("vt100", 0);
 
-  termkey_push_bytes(tk, "\e[?1;2$y", 8);
+  termkey_push_bytes(tk, "\x1b[?1;2$y", 8);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for mode report");
 
@@ -23,7 +23,7 @@ int main(int argc, char *argv[])
   is_int(mode,      1, "mode number from mode report");
   is_int(value,     2, "mode value from mode report");
 
-  termkey_push_bytes(tk, "\e[4;1$y", 7);
+  termkey_push_bytes(tk, "\x1b[4;1$y", 7);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for mode report");
 
diff --git a/t/38csi.c b/t/38csi.c
index 9d186f6..fd592d5 100644
--- a/t/38csi.c
+++ b/t/38csi.c
@@ -13,7 +13,7 @@ int main(int argc, char *argv[])
 
   tk = termkey_new_abstract("vt100", 0);
 
-  termkey_push_bytes(tk, "\e[5;25v", 7);
+  termkey_push_bytes(tk, "\x1b[5;25v", 7);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for CSI v");
 
@@ -26,14 +26,14 @@ int main(int argc, char *argv[])
   is_int(args[1],  25, "args[1] for unknown CSI");
   is_int(command, 'v', "command for unknown CSI");
 
-  termkey_push_bytes(tk, "\e[?w", 4);
+  termkey_push_bytes(tk, "\x1b[?w", 4);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for CSI ? w");
   is_int(key.type, TERMKEY_TYPE_UNKNOWN_CSI, "key.type for unknown CSI");
   is_int(termkey_interpret_csi(tk, &key, args, &nargs, &command), TERMKEY_RES_KEY, "interpret_csi yields RES_KEY");
   is_int(command, '?'<<8 | 'w', "command for unknown CSI");
 
-  termkey_push_bytes(tk, "\e[?$x", 5);
+  termkey_push_bytes(tk, "\x1b[?$x", 5);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for CSI ? $x");
   is_int(key.type, TERMKEY_TYPE_UNKNOWN_CSI, "key.type for unknown CSI");
diff --git a/t/39dcs.c b/t/39dcs.c
index c517411..f065477 100644
--- a/t/39dcs.c
+++ b/t/39dcs.c
@@ -12,7 +12,7 @@ int main(int argc, char *argv[])
   tk = termkey_new_abstract("xterm", 0);
 
   // 7bit DCS
-  termkey_push_bytes(tk, "\eP1$r1 q\e\\", 10);
+  termkey_push_bytes(tk, "\x1bP1$r1 q\x1b\\", 10);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for DCS");
 
@@ -38,7 +38,7 @@ int main(int argc, char *argv[])
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_NONE, "getkey again yields RES_NONE");
 
   // 7bit OSC
-  termkey_push_bytes(tk, "\e]15;abc\e\\", 10);
+  termkey_push_bytes(tk, "\x1b]15;abc\x1b\\", 10);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_KEY, "getkey yields RES_KEY for OSC");
 
@@ -51,7 +51,7 @@ int main(int argc, char *argv[])
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_NONE, "getkey again yields RES_NONE");
 
   // False alarm
-  termkey_push_bytes(tk, "\eP", 2);
+  termkey_push_bytes(tk, "\x1bP", 2);
 
   is_int(termkey_getkey(tk, &key), TERMKEY_RES_AGAIN, "getkey yields RES_AGAIN for false alarm");