diff --git a/.gitignore b/.gitignore
index c6439f3..b7ce3a5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,7 @@ build
 
 # misc
 .DS_Store
+
+#for test.c
+/test
+/testlog.txt
diff --git a/CMakeLists.txt b/CMakeLists.txt
index aa5178a..095e11f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,8 +2,8 @@ cmake_minimum_required(VERSION 2.6)
 project(CMoe-Counter C)
 SET(CMAKE_BUILD_TYPE "Release")
 
-# include_directories("/usr/local/include")
-# link_directories("/usr/local/lib")
+include_directories("/usr/local/include")
+link_directories("/usr/local/lib")
 
 #在编译选项中加入c99支持
 add_compile_options(-std=c99)
diff --git a/cmoe.c b/cmoe.c
index dfa16ba..188517f 100644
--- a/cmoe.c
+++ b/cmoe.c
@@ -9,6 +9,7 @@
 
 static uint32_t* items_len;
 static counter_t counter;
+static FILE* fp;
 
 static char* datfile = "dat.sp";
 static char* token = "fumiama";
@@ -19,7 +20,7 @@ static char* token = "fumiama";
 static int _headers(uint32_t content_len, const char* h, size_t hlen) {
     char buf[64];
     size_t offset = ADD_HEADER_PARAM(buf, 0, CONTENT_LEN "\r\n", content_len);
-    if(offset <= 0) return -1;
+    if (offset <= 0) return -1;
     content_len += offset+hlen;
     struct iovec iov[3] = {{&content_len, sizeof(uint32_t)}, {(void*)h, hlen}, {(void*)buf, offset}};
     return writev(1, (const struct iovec *)&iov, 3) <= 0;
@@ -36,29 +37,29 @@ static inline void http_error(errcode_enum_t code, char* msg) {
 // get_arg used malloc but has never freed
 static char* get_arg(const char* query) {
     int len = 0;
-    while(query[len] && query[len] != '&') len++;
-    if(len <= 0) return NULL;
+    while (query[len] && query[len] != '&') len++;
+    if (len <= 0) return NULL;
     char* name = malloc(len+1);
     memcpy(name, query, len);
     name[len] = 0;
     return name;
 }
 
-static int del_user(FILE* fp, SIMPLE_PB* spb) {
+static int del_user(FILE* fp, simple_pb_t* spb) {
     counter_t *d = (counter_t *)spb->target;
     uint32_t next = ftell(fp);
     uint32_t this = next - spb->real_len;
-    fseek(fp, 0, SEEK_END);
+    if (fseek(fp, 0, SEEK_END) < 0) return -2;
     uint32_t end = ftell(fp);
-    if(next == end) return ftruncate(fileno(fp), end - spb->real_len);
+    if (next == end) return ftruncate(fileno(fp), end - spb->real_len);
     uint32_t cap = end - next;
     char *data = malloc(cap);
-    if(data) {
-        fseek(fp, next, SEEK_SET);
-        if(fread(data, cap, 1, fp) == 1) {
-            if(!ftruncate(fileno(fp), end - spb->real_len)){
-                fseek(fp, this, SEEK_SET);
-                if(fwrite(data, cap, 1, fp) == 1) {
+    if (data) {
+        if (fseek(fp, next, SEEK_SET)) return -3;
+        if (fread(data, cap, 1, fp) == 1) {
+            if (!ftruncate(fileno(fp), end - spb->real_len)){
+                if (fseek(fp, this, SEEK_SET)) return -4;
+                if (fwrite(data, cap, 1, fp) == 1) {
                     free(data);
                     fflush(fp);
                     return 0;
@@ -73,34 +74,34 @@ static int del_user(FILE* fp, SIMPLE_PB* spb) {
 static inline int add_user(char* name, uint32_t count, FILE* fp) {
     counter.count = count;
     strncpy(counter.name, name, COUNTER_NAME_LEN-1);
-    fseek(fp, 0, SEEK_END);
+    if (fseek(fp, 0, SEEK_END) < 0) return -2;
     return !set_pb(fp, items_len, sizeof(counter_t), &counter);
 }
 
 static inline uint32_t get_content_len(int isbig, uint16_t* len_type, char* cntstr) {
     uint32_t len = sizeof(svg_small) // small & big has the same len
         + sizeof(svg_tail) - 1;
-    for(int i = 0; cntstr[i]; i++) {
+    for (int i = 0; cntstr[i]; i++) {
         len += len_type[cntstr[i] - '0'] + (sizeof(img_slot_front) + sizeof(img_slot_rear) - 2);
-        if(i > 0) len++;
-        if(i > 2-isbig) len++;
+        if (i > 0) len++;
+        if (i > 2-isbig) len++;
     }
     return len;
 }
 
 #define has_next(fp, ch) ((ch=getc(fp)),(feof(fp)?0:(ungetc(ch,fp),1)))
-#define set_type(name, t, l) if(!strcmp(theme, name)) {\
+#define set_type(name, t, l) if (!strcmp(theme, name)) {\
                                 theme_type = (char**)t;\
                                 len_type = (uint16_t*)l;\
                             }
 static void return_count(FILE* fp, char* name, char* theme) {
     int ch, exist = 0, user_exist = 0;
-    char buf[sizeof(SIMPLE_PB)+sizeof(counter_t)];
-    while(has_next(fp, ch)) {
-        SIMPLE_PB *spb = read_pb_into(fp, (SIMPLE_PB*)buf);
+    char buf[sizeof(simple_pb_t)+sizeof(counter_t)];
+    while (has_next(fp, ch)) {
+        simple_pb_t *spb = read_pb_into(fp, (simple_pb_t*)buf);
         counter_t *d = (counter_t *)spb->target;
         if (strcmp(name, d->name)) continue;
-        if(del_user(fp, spb)) {
+        if (del_user(fp, spb)) {
             http_error(HTTP500, "Unable to Delete Old Data.");
             return;
         }
@@ -111,14 +112,14 @@ static void return_count(FILE* fp, char* name, char* theme) {
         char cntstrbuf[11];
         sprintf(cntstrbuf, "%010u", d->count);
         char* cntstr = cntstrbuf;
-        for(int i = 0; i < 10; i++) if(cntstrbuf[i] != '0') {
-            if(i > 2) cntstr = cntstrbuf+i-2;
+        for (int i = 0; i < 10; i++) if (cntstrbuf[i] != '0') {
+            if (i > 2) cntstr = cntstrbuf+i-2;
             break;
         }
         int isbig = 0;
         char** theme_type = (char**)mb;
         uint16_t* len_type = (uint16_t*)mbl;
-        if(theme) {
+        if (theme) {
             set_type("mbh", mbh, mbhl) else
             set_type("r34", r34, r34l) else
             set_type("gb", gb, gbl) else
@@ -127,7 +128,7 @@ static void return_count(FILE* fp, char* name, char* theme) {
         }
         int w, h;
         char *head;
-        if(isbig) {
+        if (isbig) {
             w = W_BIG;
             h = H_BIG;
             head = (char*)svg_big;
@@ -137,12 +138,12 @@ static void return_count(FILE* fp, char* name, char* theme) {
             h = H_SMALL;
             head = (char*)svg_small;
         }
-        if(headers(get_content_len(isbig, len_type, cntstr), "image/svg+xml")) {
+        if (headers(get_content_len(isbig, len_type, cntstr), "image/svg+xml")) {
             write(1, "\0\0\0\0", 4);
             return;
         }
         printf(head, w*(10+cntstrbuf-cntstr));
-        for(int i = 0; cntstr[i]; i++) {
+        for (int i = 0; cntstr[i]; i++) {
             printf(img_slot_front, w * i, w, h);
             int n = cntstr[i] - '0';
             fwrite(theme_type[n], len_type[n], 1, stdout);
@@ -156,9 +157,9 @@ static void return_count(FILE* fp, char* name, char* theme) {
 
 static int name_exist(FILE* fp, char* name) {
     int ch, exist = 0;
-    char buf[sizeof(SIMPLE_PB)+sizeof(counter_t)];
-    while(has_next(fp, ch)) {
-        SIMPLE_PB *spb = read_pb_into(fp, (SIMPLE_PB*)buf);
+    char buf[sizeof(simple_pb_t)+sizeof(counter_t)];
+    while (has_next(fp, ch)) {
+        simple_pb_t *spb = read_pb_into(fp, (simple_pb_t*)buf);
         counter_t *d = (counter_t *)spb->target;
         if (!strcmp(name, d->name)) return 1;
     }
@@ -170,47 +171,46 @@ static int name_exist(FILE* fp, char* name) {
 #define QS (argv[2])
 // Usage: cmoe method query_string
 int main(int argc, char **argv) {
-    if(argc != 3) {
+    if (argc != 3) {
         http_error(HTTP500, "Argument Count Error.");
         return -1;
     }
     char* str = getenv("DATFILE");
-    if(str != NULL) datfile = str;
+    if (str != NULL) datfile = str;
     str = getenv("TOKEN");
-    if(str != NULL) token = str;
+    if (str != NULL) token = str;
     char* name = strstr(QS, "name=");
     items_len = align_struct(sizeof(counter_t), 2, &counter.name, &counter.count);
-    if(!items_len) {
+    if (!items_len) {
         http_error(HTTP500, "Align Struct Error.");
         return 2;
     }
-    if(!name) {
+    if (!name) {
         http_error(HTTP400, "Name Argument Notfound.");
         return 3;
     }
     name = get_arg(name + 5);
-    if(!name) {
+    if (!name) {
         http_error(HTTP400, "Null Name Argument.");
         return 4;
     }
     char* theme = strstr(QS, "theme=");
-    if(theme) {
+    if (theme) {
         theme = get_arg(theme + 6);
     }
     char* reg = strstr(QS, "reg=");
-    int fd; FILE* fp;
+    int fd; 
     if (!reg) {
-        if((fd=create_or_open(datfile)) < 0) {
+        if ((fd=create_or_open(datfile)) < 0) {
             http_error(HTTP500, "Open File Error.");
             return -2;
         }
-        if(flock(fd, LOCK_EX)) {
+        if (flock(fd, LOCK_EX)) {
             http_error(HTTP500, "Lock File Error.");
             return -3;
         }
         fp = fdopen(fd, "rb+");
         return_count(fp, name, theme);
-        fflush(fp); flock(fd, LOCK_UN); close(fd);
         return 0;
     }
     reg = get_arg(reg + 4);
@@ -218,31 +218,33 @@ int main(int argc, char **argv) {
         http_error(HTTP400, "Null Register Token.");
         return 5;
     }
-    if(strcmp(reg, token)) {
+    if (strcmp(reg, token)) {
         http_error(HTTP400, "Token Error.");
         return 6;
     }
-    if((fd=create_or_open(datfile)) < 0) {
+    if ((fd=create_or_open(datfile)) < 0) {
         http_error(HTTP500, "Open File Error.");
         return -4;
     }
-    if(flock(fd, LOCK_EX)) {
+    if (flock(fd, LOCK_EX)) {
         http_error(HTTP500, "Lock File Error.");
         return -5;
     }
     fp = fdopen(fd, "rb+");
-    if(name_exist(fp, name)) {
-        fflush(fp); flock(fd, LOCK_UN); close(fd);
+    if (name_exist(fp, name)) {
         http_error(HTTP400, "Name Exist.");
         return 7;
     }
     fseek(fp, 0, SEEK_END);
     add_user(name, 0, fp);
-    fflush(fp); flock(fd, LOCK_UN); close(fd);
     char* msg = "<P>Success.\r\n";
-    if(headers(strlen(msg), "text/html")) {
+    if (headers(strlen(msg), "text/html")) {
         write(1, "\0\0\0\0", 4);
         return 8;
     }
     return write(1, msg, strlen(msg)) <= 0;
 }
+
+static void __attribute__((destructor)) defer_close_fp() {
+    if (fp) fclose(fp);
+}
diff --git a/editor.c b/editor.c
index 2b1c7ca..39e37fd 100644
--- a/editor.c
+++ b/editor.c
@@ -10,9 +10,9 @@ static counter_t counter;
 
 static FILE* fp;
 
-static char buf[sizeof(SIMPLE_PB)+sizeof(counter_t)];
+static char buf[sizeof(simple_pb_t)+sizeof(counter_t)];
 
-static int del_user(FILE* fp, SIMPLE_PB* spb) {
+static int del_user(FILE* fp, simple_pb_t* spb) {
     counter_t *d = (counter_t *)spb->target;
     uint32_t next = ftell(fp);
     uint32_t this = next - spb->real_len;
@@ -99,7 +99,7 @@ int main(int argc, char** argv) {
                     return 5;
                 }
                 while(has_next(fp, c)) {
-                    SIMPLE_PB *spb = read_pb_into(fp, (SIMPLE_PB*)buf);
+                    simple_pb_t *spb = read_pb_into(fp, (simple_pb_t*)buf);
                     counter_t *d = (counter_t *)spb->target;
                     if (strcmp(counter.name, d->name)) continue;
                     if(del_user(fp, spb)) {
@@ -127,7 +127,7 @@ int main(int argc, char** argv) {
                     return 7;
                 }
                 while(has_next(fp, c)) {
-                    SIMPLE_PB *spb = read_pb_into(fp, (SIMPLE_PB*)buf);
+                    simple_pb_t *spb = read_pb_into(fp, (simple_pb_t*)buf);
                     counter_t *d = (counter_t *)spb->target;
                     if (strstr(d->name, counter.name)) {
                         if(del_user(fp, spb)) {
@@ -151,7 +151,7 @@ int main(int argc, char** argv) {
                     return 5;
                 }
                 while(has_next(fp, c)) {
-                    SIMPLE_PB *spb = read_pb_into(fp, (SIMPLE_PB*)buf);
+                    simple_pb_t *spb = read_pb_into(fp, (simple_pb_t*)buf);
                     counter_t *d = (counter_t *)spb->target;
                     if (strcmp(counter.name, d->name)) continue;
                     printf("user '%s' = %u.\n", d->name, d->count);
@@ -170,7 +170,7 @@ int main(int argc, char** argv) {
                     return 7;
                 }
                 while(has_next(fp, c)) {
-                    SIMPLE_PB *spb = read_pb_into(fp, (SIMPLE_PB*)buf);
+                    simple_pb_t *spb = read_pb_into(fp, (simple_pb_t*)buf);
                     counter_t *d = (counter_t *)spb->target;
                     if (d->count < counter.count) {
                         printf("'%s' = %u\n", d->name, d->count);
@@ -195,7 +195,7 @@ int main(int argc, char** argv) {
                     return 7;
                 }
                 while(has_next(fp, c)) {
-                    SIMPLE_PB *spb = read_pb_into(fp, (SIMPLE_PB*)buf);
+                    simple_pb_t *spb = read_pb_into(fp, (simple_pb_t*)buf);
                     counter_t *d = (counter_t *)spb->target;
                     if (d->count < counter.count) {
                         if(del_user(fp, spb)) {
@@ -222,7 +222,7 @@ int main(int argc, char** argv) {
                     return 7;
                 }
                 while(has_next(fp, c)) {
-                    SIMPLE_PB *spb = read_pb_into(fp, (SIMPLE_PB*)buf);
+                    simple_pb_t *spb = read_pb_into(fp, (simple_pb_t*)buf);
                     counter_t *d = (counter_t *)spb->target;
                     if (!counter.name[0] || strstr(d->name, counter.name)) {
                         printf("'%s' = %u\n", d->name, d->count);
diff --git a/test.c b/test.c
new file mode 100644
index 0000000..f084b12
--- /dev/null
+++ b/test.c
@@ -0,0 +1,89 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+#include <time.h>
+#include <sys/file.h>
+#include <sys/uio.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#define THREADCNT 1024
+
+int pipefds[2*THREADCNT];
+
+#define create_or_open(filename) (open(filename, O_CREAT|O_RDWR, 0600))
+
+int main(int argc, char** argv) {
+    printf("run: ");
+    for (int i = 0; i < argc; i++) {
+        printf("%s ", argv[i]);
+    }
+    puts(".");
+    if (argc == 1) {
+        for (int i = 0; i < THREADCNT; i++) {
+            if (pipe(&pipefds[i*2]) < 0) {
+                perror("pipe");
+                exit(EXIT_FAILURE);
+            }
+            pid_t pid = fork();
+            if (pid < 0) {
+                perror("fork");
+                exit(EXIT_FAILURE);
+            }
+            char buf[5];
+            sprintf(buf, "%04d", i);
+            if (!pid) {
+                printf("[%s] start@[%d,%d]=(%d,%d).\n", buf, i*2, i*2+1, pipefds[i*2], pipefds[i*2+1]);
+                dup2(pipefds[i*2+1], STDOUT_FILENO);
+                close(pipefds[i*2]);
+                //printf("[%s] sub close@%d=%d, execl.\n", buf, i*2, pipefds[i*2]);
+                execl("./test", "./test", buf, NULL);
+                perror("execl");
+                exit(EXIT_FAILURE); // a success execl will never return
+            } else {
+                close(pipefds[i*2+1]);
+                //printf("[%s] main close@%d=%d, read.\n", buf, i*2+1, pipefds[i*2+1]);
+            }
+        }
+        if (!fork()) {
+            char buf[128]; ssize_t n;
+            for (int i = 0; i < THREADCNT; i++) {
+                do {
+                    n = read(pipefds[i*2], buf, sizeof(buf));
+                    if (n < 0) {
+                        perror("read");
+                        exit(EXIT_FAILURE);
+                    }
+                    if (n > 0) {
+                        buf[n] = 0;
+                        printf("%zu> %s", n, buf);
+                    }
+                } while (n > 0);
+            }
+        } else waitpid(-1, NULL, 0);
+        return 0;
+    }
+    usleep(rand()%1000);
+    int fd = create_or_open("testlog.txt");
+    if (fd < 0) {
+        perror("open");
+        exit(EXIT_FAILURE);
+    }
+    if(flock(fd, LOCK_EX)) {
+        perror("flock");
+        exit(EXIT_FAILURE);
+    }
+    FILE* fp = fdopen(fd, "rb+");
+    fseek(fp, 0, SEEK_END);
+    fputs(argv[1], fp);
+    putc('\n', fp);
+    srand(*(uint32_t*)argv[1]);
+    int rndslp = rand()%1000;
+    printf("[%s] get lock. sleep %d ms\n", argv[1], rndslp);
+    usleep(rndslp);
+    printf("[%s] release lock.\n", argv[1]);
+    fclose(fp);
+    //close(fd);
+    return 0;
+}
diff --git a/test.sh b/test.sh
new file mode 100755
index 0000000..e4d468f
--- /dev/null
+++ b/test.sh
@@ -0,0 +1,21 @@
+#!/bin/bash
+
+cd build
+./cmoe GET "name=fumiama&reg=fumiama"
+./cmoe GET "name=fumiam&reg=fumiama"
+./cmoe GET "name=fumia&reg=fumiama"
+./cmoe GET "name=fumi&reg=fumiama"
+./cmoe GET "name=fum&reg=fumiama"
+./cmoe GET "name=fu&reg=fumiama"
+./cmoe GET "name=f&reg=fumiama"
+
+for ((i=0; i<$1; i++))
+do
+  ./cmoe GET "name=fumiama&theme=r34" &
+  ./cmoe GET "name=fumiam&theme=r34" &
+  ./cmoe GET "name=fumia&theme=r34" &
+  ./cmoe GET "name=fumi&theme=r34" &
+  ./cmoe GET "name=fum&theme=r34" &
+  ./cmoe GET "name=fu&theme=r34" &
+  ./cmoe GET "name=f&theme=r34" &
+done