diff --git a/src/calibre/utils/lzx/lzc.c b/src/calibre/utils/lzx/lzc.c
index 4466e5a575..e1f153d97c 100644
--- a/src/calibre/utils/lzx/lzc.c
+++ b/src/calibre/utils/lzx/lzc.c
@@ -74,7 +74,7 @@ void lz_init(lz_info *lzi, int wsize, int max_dist,
   lzi->user_data = user_data;
   lzi->frame_size = frame_size;
   lzi->lentab = calloc(lzi->block_buf_size + 1, sizeof(int));
-  lzi->prevtab = calloc(lzi->block_buf_size + 1, sizeof(u_char *));
+  lzi->prevtab = calloc(lzi->block_buf_size + 1, sizeof(unsigned char *));
   lzi->analysis_valid = 0;
 }
 
@@ -102,7 +102,7 @@ typedef struct lz_user_data
   int R0, R1, R2;
 } lz_user_data;
 
-int tmp_get_chars(lz_info *lzi, int n, u_char *buf)
+int tmp_get_chars(lz_info *lzi, int n, unsigned char *buf)
 {
   lz_user_data *lzud = (lz_user_data *)lzi->user_data;
   return fread(buf, 1, n, lzud->infile);
@@ -119,7 +119,7 @@ int tmp_output_match(lz_info *lzi, int match_pos, int match_len)
   return 0;
 }
 
-void tmp_output_literal(lz_info *lzi, u_char ch)
+void tmp_output_literal(lz_info *lzi, unsigned char ch)
 {
   lz_user_data *lzud = (lz_user_data *)lzi->user_data;
   fprintf(lzud->outfile, "'%c'", ch);
@@ -137,7 +137,7 @@ int main(int argc, char *argv[])
 }
 #endif
 
-__inline__ int lz_left_to_process(lz_info *lzi)
+int lz_left_to_process(lz_info *lzi)
 {
   return lzi->chars_in_buf - lzi->block_loc;
 }
@@ -146,7 +146,7 @@ static void
 fill_blockbuf(lz_info *lzi, int maxchars)
 {
   int toread;
-  u_char *readhere;
+  unsigned char *readhere;
   int nread;
 
   if (lzi->eofcount) return;
@@ -163,10 +163,10 @@ fill_blockbuf(lz_info *lzi, int maxchars)
 static void lz_analyze_block(lz_info *lzi)
 {
   int *lentab, *lenp;
-  u_char **prevtab, **prevp;
-  u_char *bbp, *bbe;
-  u_char *chartab[256];
-  u_char *cursor;
+  unsigned char **prevtab, **prevp;
+  unsigned char *bbp, *bbe;
+  unsigned char *chartab[256];
+  unsigned char *cursor;
   int prevlen;
   int ch;
   int maxlen;
@@ -287,9 +287,9 @@ void lz_stop_compressing(lz_info *lzi)
 int lz_compress(lz_info *lzi, int nchars) 
 {
 
-  u_char *bbp, *bbe;
+  unsigned char *bbp, *bbe;
   int *lentab, *lenp;
-  u_char **prevtab, **prevp;
+  unsigned char **prevtab, **prevp;
   int len;
   int holdback;
   short trimmed;
diff --git a/src/calibre/utils/lzx/lzc.h b/src/calibre/utils/lzx/lzc.h
index a721fede60..8a24f2c090 100644
--- a/src/calibre/utils/lzx/lzc.h
+++ b/src/calibre/utils/lzx/lzc.h
@@ -16,24 +16,24 @@
     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
 typedef struct lz_info lz_info;
-typedef int (*get_chars_t)(lz_info *lzi, int n, u_char *buf);
+typedef int (*get_chars_t)(lz_info *lzi, int n, unsigned char *buf);
 typedef int (*output_match_t)(lz_info *lzi, int match_pos, int match_len);
-typedef void (*output_literal_t)(lz_info *lzi, u_char ch);
+typedef void (*output_literal_t)(lz_info *lzi, unsigned char ch);
 
 struct lz_info
 {
   int wsize; /* window size in bytes */
   int max_match; /* size of longest match in bytes */
   int min_match;
-  u_char *block_buf;
-  u_char *block_bufe;
+  unsigned char *block_buf;
+  unsigned char *block_bufe;
   int block_buf_size;
   int chars_in_buf;
   int cur_loc;            /* location within stream */
   int block_loc;
   int frame_size;
   int max_dist;
-  u_char **prevtab;
+  unsigned char **prevtab;
   int *lentab;
   short eofcount;
   short stop;
diff --git a/src/calibre/utils/lzx/lzxc.c b/src/calibre/utils/lzx/lzxc.c
index ac1a5ed2a1..1617e544d2 100644
--- a/src/calibre/utils/lzx/lzxc.c
+++ b/src/calibre/utils/lzx/lzxc.c
@@ -79,7 +79,7 @@
 /* as corrected by Caie */
 short num_position_slots[] = {30, 32, 34, 36, 38, 42, 50};
 unsigned long position_base[51];
-u_char extra_bits[52];
+unsigned char extra_bits[52];
 double rloge2;
 
 typedef struct ih_elem {
@@ -459,7 +459,7 @@ struct lzxc_data
 };
 
 static int
-lzx_get_chars(lz_info *lzi, int n, u_char *buf)
+lzx_get_chars(lz_info *lzi, int n, unsigned char *buf)
 {
   /* force lz compression to stop after every block */
   int chars_read;
@@ -504,9 +504,9 @@ lzx_get_chars(lz_info *lzi, int n, u_char *buf)
 #ifdef NONSLIDE
 static int find_match_at(lz_info *lzi, int loc, int match_len, int *match_locp)
 {
-  u_char *matchb;
-  u_char *nmatchb;
-  u_char *c1, *c2;
+  unsigned char *matchb;
+  unsigned char *nmatchb;
+  unsigned char *c1, *c2;
   int j;
 
   if (-*match_locp == loc) return -1;
@@ -531,9 +531,9 @@ static int find_match_at(lz_info *lzi, int loc, int match_len, int *match_locp)
 #else
 static int find_match_at(lz_info *lzi, int loc, int match_len, int *match_locp)
 {
-  u_char *matchb;
-  u_char *nmatchb;
-  u_char *c1, *c2;
+  unsigned char *matchb;
+  unsigned char *nmatchb;
+  unsigned char *c1, *c2;
   int j;
 
   if (-*match_locp == loc) return -1;
@@ -798,7 +798,7 @@ lzx_output_match(lz_info *lzi, int match_pos, int match_len)
 }
 
 static void 
-lzx_output_literal(lz_info *lzi, u_char ch)
+lzx_output_literal(lz_info *lzi, unsigned char ch)
 {
   lzxc_data *lzud = (lzxc_data *)lzi->user_data;
 
@@ -961,15 +961,15 @@ lzx_write_compressed_tree(struct lzxc_data *lzxd,
 			  struct huff_entry *tree, uint8_t *prevlengths,
 			  int treesize)
 {
-  u_char *codes;
-  u_char *runs;
+  unsigned char *codes;
+  unsigned char *runs;
   int freqs[LZX_PRETREE_SIZE];
   int cur_run;
   int last_len;
   huff_entry pretree[20];
-  u_char *codep;
-  u_char *codee;
-  u_char *runp;
+  unsigned char *codep;
+  unsigned char *codee;
+  unsigned char *runp;
   int excess;
   int i;
   int cur_code;
diff --git a/src/calibre/utils/lzx/lzxc.h b/src/calibre/utils/lzx/lzxc.h
index fd1f7d81e5..30da460a81 100644
--- a/src/calibre/utils/lzx/lzxc.h
+++ b/src/calibre/utils/lzx/lzxc.h
@@ -17,7 +17,7 @@
 */
 
 #ifdef _MSC_VER
-#include "stdint.h"
+#include "msstdint.h"
 #endif
 
 typedef struct lzxc_data lzxc_data;