diff --git a/list.c b/list.c
index fbe832b..8a10575 100644
--- a/list.c
+++ b/list.c
@@ -2,6 +2,7 @@
 
 #include <getopt.h>
 
+void pixz_list(bool tar);
 
 #pragma mark FUNCTION DEFINITIONS
 
@@ -31,6 +32,11 @@ int main(int argc, char **argv) {
         die("Usage: %s -f [FILE]", progname);
     }
     
+    pixz_list(tar);
+    return 0;
+}
+
+void pixz_list(bool tar) {
     decode_index();
     lzma_index_iter iter;
     lzma_index_iter_init(&iter, gIndex);
@@ -48,6 +54,4 @@ int main(int argc, char **argv) {
     
     lzma_index_end(gIndex, NULL);
     lzma_end(&gStream);
-    
-    return 0;
 }
diff --git a/pixz.h b/pixz.h
index 630cbfd..7aa445d 100644
--- a/pixz.h
+++ b/pixz.h
@@ -20,6 +20,13 @@
 
 #define CHUNKSIZE 4096
 
+#define DEBUG 1
+#if DEBUG
+    #define debug(str, ...) fprintf(stderr, str "\n", ##__VA_ARGS__)
+#else
+    #define debug(...)
+#endif
+
 
 #pragma mark UTILS
 
diff --git a/read.c b/read.c
index 7331d3e..d447a21 100644
--- a/read.c
+++ b/read.c
@@ -5,13 +5,6 @@
 
 #include <getopt.h>
 
-#define DEBUG 0
-#if DEBUG
-    #define debug(str, ...) fprintf(stderr, str "\n", ##__VA_ARGS__)
-#else
-    #define debug(...)
-#endif
-
 
 #pragma mark DECLARE WANTED
 
@@ -64,7 +57,8 @@ static lzma_vli gFileIndexOffset = 0;
 static size_t gBlockInSize = 0, gBlockOutSize = 0;
 
 static void set_block_sizes(void);
-static void pixz_read(bool verify, size_t nspecs, char **specs);
+
+void pixz_read(bool verify, size_t nspecs, char **specs);
 
 
 #pragma mark MAIN
@@ -93,7 +87,7 @@ int main(int argc, char **argv) {
     return 0;
 }
     
-static void pixz_read(bool verify, size_t nspecs, char **specs) {
+void pixz_read(bool verify, size_t nspecs, char **specs) {
     decode_index();
     if (verify)
         gFileIndexOffset = read_file_index(0);
@@ -419,7 +413,7 @@ static ssize_t tar_read(struct archive *ar, void *ref, const void **bufp) {
         off = 0;
         size = ib->outsize;
     }
-    debug("tar off = %zu, size = %zu", off, size);
+    debug("tar off = %llu, size = %zu", (unsigned long long)off, size);
     
     gArLastOffset = off;
     gArLastSize = size;
diff --git a/write.c b/write.c
index 7e3ce77..055ec35 100644
--- a/write.c
+++ b/write.c
@@ -17,10 +17,7 @@ struct io_block_t {
 
 #pragma mark GLOBALS
 
-#define DEBUG 0
-
 static bool gTar = true;
-static uint32_t gPreset = LZMA_PRESET_DEFAULT;
 
 static size_t gBlockInSize = 0, gBlockOutSize = 0;
 
@@ -40,12 +37,6 @@ static size_t gFileIndexBufPos = 0;
 
 #pragma mark FUNCTION DECLARATIONS
 
-#if DEBUG
-    #define debug(str, ...) fprintf(stderr, str "\n", ##__VA_ARGS__)
-#else
-    #define debug(...)
-#endif
-
 static void read_thread();
 static void encode_thread(size_t thnum);
 static void *block_create();
@@ -66,22 +57,25 @@ static void write_file_index(void);
 static void write_file_index_bytes(size_t size, uint8_t *buf);
 static void write_file_index_buf(lzma_action action);
 
+void pixz_write(bool tar, uint32_t level);
 
 #pragma mark FUNCTION DEFINITIONS
 
 int main(int argc, char **argv) {
     char *progname = argv[0];
+    uint32_t level = LZMA_PRESET_DEFAULT;
+    bool tar = true;
     debug("launch");
     
     int ch;
     while ((ch = getopt(argc, argv, "t0123456789")) != -1) {
         switch (ch) {
             case 't':
-                gTar = false;
+                tar = false;
                 break;
             default:
                 if (optopt >= '0' && optopt <= '9') {
-                    gPreset = optopt - '0';
+                    level = optopt - '0';
                 } else {
                     die("Unknown option");
                 }
@@ -89,7 +83,6 @@ int main(int argc, char **argv) {
     }
     argc -= optind - 1;
     argv += optind - 1;
-    
 
     if (argc == 1) {
         gInFile = stdin;
@@ -103,9 +96,15 @@ int main(int argc, char **argv) {
         die("Usage: %s [-t] [INPUT OUTPUT]", progname);
     }
     
+    pixz_write(tar, level);
+}
+    
+void pixz_write(bool tar, uint32_t level) {
+    gTar = tar;
+    
     // xz options
     lzma_options_lzma lzma_opts;
-    if (lzma_lzma_preset(&lzma_opts, gPreset))
+    if (lzma_lzma_preset(&lzma_opts, level))
         die("Error setting lzma options");
     gFilters[0] = (lzma_filter){ .id = LZMA_FILTER_LZMA2,
             .options = &lzma_opts };
@@ -149,7 +148,6 @@ int main(int argc, char **argv) {
     pipeline_destroy();
     
     debug("exit");
-    return 0;
 }