diff --git a/experiment/README.md b/experiment/README.md
index 0f27c4e..73dfdaa 100644
--- a/experiment/README.md
+++ b/experiment/README.md
@@ -22,8 +22,8 @@ futiles.
 
 ## système de cache
 
-new: Mon Jul 17 12:49:20 UTC 2023
+`new: Mon Jul 17 12:49:20 UTC 2023`
 
 En cours : définition d'à peu-près tout ce qu'il reste à faire
 pour avoir quelque chose qui fonctionne.
-Plus d'information dans le [.h](cachegen.h).
+Plus d'information dans le [.h](cachengn.h).
diff --git a/experiment/cachengn.c b/experiment/cachengn.c
index 3a1f67b..b7e4026 100644
--- a/experiment/cachengn.c
+++ b/experiment/cachengn.c
@@ -3,23 +3,143 @@
  */
 
 #include  <stdio.h>
+#include  <unistd.h>
+#include  <sys/time.h>
+#include  <stdlib.h>
+#include  <string.h>
 
+#include  "../floatimg.h"
 #include  "cachengn.h"
 
+extern int		verbosity;
+
+static int		nombre_slots = -1;
+static int		index_slot   = -1;
+static FimgCacheEntry	*le_cache    = NULL;
+
 /* ------------------------------------------------------------ */
 
 void cachengn_print_version(int k)
 {
 
-printf("this is the version ZERO !!!\n");
+printf("\t!!! this is the version ZERO !!!\n");
 
+fprintf(stderr, "sizeof cache entry: %ld\n", sizeof(FimgCacheEntry));
+
+if (k) fimg_print_version(0);
 }
-
 /* ------------------------------------------------------------ */
-int init_empty_cache(int iw, int ih, int szc, int nbre)
+/*
+ *
+ */
+int init_empty_cache(int iw, int ih, int szc, int wtfparam)
 {
-return -1;
+int		idx;
+
+fprintf(stderr, ">>> %s ( %d %d   %d %d )\n", __func__,
+			iw, ih,  szc, wtfparam);
+
+/* MOLLYGUARD : don't init TWICE, please */
+if (NULL != le_cache) {
+	fprintf(stderr, "%s: there is a cache at %p\n", __func__,
+						le_cache);
+	return -2;
+	}
+
+/* allocate an prepare memory */
+if ( NULL==(le_cache=calloc(szc, sizeof(FimgCacheEntry))) ) {
+	fprintf(stderr, "%s: no memory, sorry...\n", __func__);
+	return -3;
+	}
+fprintf(stderr, "    slot array at %p\n", le_cache);
+for (idx=0; idx<szc; idx++) {
+	le_cache[idx].flags = 0xF0;
+	le_cache[idx].index = idx;
+	}
+
+/* update private cache metadata */
+nombre_slots = szc;
+
+return 0;
 }
 
 /* ------------------------------------------------------------ */
+/*
+ *
+ */
+FloatImg *give_me_thiz_picz(char *fname, int notused)
+{
+int			idx, foo, freeslot;
+FloatImg		img;
+char			*nptr;
+
+fprintf(stderr, ">>> %s ( '%s' %d )\n", __func__, fname, notused);
+
+/* please add molly guard ! */
+
+if (notused)
+	fprintf(stderr, "in %s, notused was %d\n", __func__, notused);
+
+/* is the floatimg already in the cahce ? */
+for (idx=0; idx<nombre_slots; idx++) {
+	nptr = le_cache[idx].filename;
+	if (NULL!=nptr && (! strcmp(fname, nptr))) {
+		fprintf(stderr, "found '%s' at %d\n", nptr, idx);
+		return le_cache[idx].image;
+		}
+	}
+
+/* we not have this picture in ou cache, so we need a free
+   slot for it */
+freeslot = -1;
+for (idx=0; idx<nombre_slots; idx++) {
+	if (NULL==le_cache[idx].image) {
+		freeslot = idx;
+		break;
+		}
+	}
+fprintf(stderr, "freeslot = %d\n", freeslot);
+
+/* check if we can read this file */
+foo = access(fname, R_OK);			/* XXX */
+if (foo) {
+	perror(__FILE__ ": give_me_thiz_picz");
+	return NULL;
+	}
+
+/* try to load the requested file */
+foo = fimg_create_from_dump(fname, &img);
+if (foo) {
+	fprintf(stderr, "oups on %s\n", fname);
+	return NULL;
+	}
+/* OK we have all the pixels in core memorey */
+
+
+return NULL;
+}
+/* ------------------------------------------------------------ */
+/*
+ *
+ */
+int liste_le_cache(unsigned int flags)
+{
+int		idx;
+
+fprintf(stderr, ">>> %s ( Ox%X )\n", __func__, flags);
+
+/* please add molly guard here */
+
+fprintf(stderr, "cache at %p : %d slots, idx = %d\n",
+				le_cache, nombre_slots, index_slot);
+
+for (idx=0; idx<nombre_slots; idx++) {
+	fprintf(stderr, "%5d    ", idx);
+	fprintf(stderr, "0x%02x ", le_cache[idx].flags);
+	fprintf(stderr, "%p     ", le_cache[idx].image);
+	fprintf(stderr, "%s\n",    le_cache[idx].filename);
+	}
+
+return 0;
+}
 /* ------------------------------------------------------------ */
diff --git a/experiment/cachengn.h b/experiment/cachengn.h
index 6136ee0..a2d4f0d 100644
--- a/experiment/cachengn.h
+++ b/experiment/cachengn.h
@@ -4,4 +4,26 @@
 
 void cachengn_print_version(int k);
 
+typedef struct {
+	int		flags;
+	char		*filename;
+	FloatImg	*image;
+	int		index;
+	} FimgCacheEntry;
+
+
+/*
+ *		parameters:
+ *	- iw, ik   : image size
+ *	- szc      : number of slots
+ *	- nbre     : WTF isthat?
+ */
 int init_empty_cache(int iw, int ih, int szc, int nbre);
+
+
+/* /!\ the floatimg returned must be view as readonly */
+FloatImg *give_me_thiz_picz(char *fname, int notused);
+
+
+/* utilities functions */
+int liste_le_cache(unsigned int flags);
diff --git a/experiment/tcache.c b/experiment/tcache.c
index 5a8880b..e84a0f3 100644
--- a/experiment/tcache.c
+++ b/experiment/tcache.c
@@ -3,24 +3,45 @@
  */
 
 #include  <stdio.h>
+#include  <sys/time.h>
 
+#include  "../floatimg.h"
 #include  "cachengn.h"
 
+int		verbosity;
+
 #define IMGW	320
 #define IMGH	240
-#define SIZE	20
+
+#define SIZE	5		// number of slots
 #define NBRI	1000
 
 /* ------------------------------------------------------------ */
 int main(int argc, char *argv[])
 {
 int		foo;
+FloatImg	*picz;
+char		*fname = "quux.fimg";
 
-fprintf(stderr, "Test of the cache engin - %s %s\n", __DATE__, __TIME__);
+fprintf(stderr, "\nTest of the cache engin - %s %s\n",
+					__DATE__, __TIME__);
 cachengn_print_version(1);
 
 foo = init_empty_cache(IMGW, IMGH, SIZE, NBRI);
-fprintf(stderr, "init_empty_cache --> %d\n", foo);
+fprintf(stderr, "    init_empty_cache --> %d\n", foo);
+
+foo = liste_le_cache((unsigned int)'U');
+fprintf(stderr, "    liste le cache --> %d\n", foo);
+
+picz = give_me_thiz_picz(fname, 0);
+if (NULL == picz) {
+	fprintf(stderr, "    error 'givemeapicz' on '%s'\n", fname);
+	}
+
+picz = give_me_thiz_picz(fname, 0);
+if (NULL == picz) {
+	fprintf(stderr, "    error 'givemeapicz' on '%s'\n", fname);
+	}
 
 return 0;
 }