diff --git a/example/src/split_log_date.rs b/example/src/split_log_date.rs
index e0e1af7..1f38df1 100644
--- a/example/src/split_log_date.rs
+++ b/example/src/split_log_date.rs
@@ -1,10 +1,76 @@
 use fast_log::config::Config;
 use fast_log::consts::LogSize;
-use fast_log::plugin::keep::{KeepAll, KeepNum};
-use fast_log::plugin::packer::{LogDatePacker, LogPacker};
+use fast_log::error::LogError;
+use fast_log::plugin::file_split::Packer;
+use fast_log::plugin::keep::KeepNum;
+use std::fs::{File, OpenOptions};
+use std::io::{Read, Write};
+use std::path::Path;
 use std::thread::sleep;
 use std::time::Duration;
 
+///pack by an date
+#[derive(Clone)]
+pub struct LogDatePacker {}
+
+impl LogDatePacker {
+    pub fn log_name_create_by_time(
+        &self,
+        first_file_path: &str,
+        date: fastdate::DateTime,
+    ) -> String {
+        let path = Path::new(first_file_path);
+        let file_name = path
+            .file_name()
+            .unwrap_or_default()
+            .to_str()
+            .unwrap_or_default()
+            .to_string();
+        let mut new_log_name = date.to_string().replace(" ", "T").replace(":", "-");
+        new_log_name.push_str(".");
+        new_log_name.push_str(self.pack_name());
+        new_log_name = first_file_path.trim_end_matches(&file_name).to_string() + &new_log_name;
+        return new_log_name;
+    }
+}
+impl Packer for LogDatePacker {
+    fn pack_name(&self) -> &'static str {
+        "log"
+    }
+
+    fn do_pack(&self, mut log_file: File, log_file_path: &str) -> Result<bool, LogError> {
+        //do nothing,and not remove file
+        let now = fastdate::DateTime::now()
+            .set_hour(0)
+            .set_min(0)
+            .set_sec(0)
+            .set_nano(0);
+        let name = self.log_name_create_by_time(log_file_path, now);
+        let mut f = OpenOptions::new()
+            .write(true)
+            .read(true)
+            .append(true)
+            .open(&name);
+        if let Ok(mut f) = f {
+            //append to file
+            let mut data = vec![];
+            log_file.read_to_end(&mut data)?;
+            f.write_all(&data)?;
+            std::fs::remove_file(log_file_path)?;
+        } else {
+            //create file
+            f = OpenOptions::new().write(true).create(true).open(name);
+            if let Ok(mut f) = f {
+                let mut data = vec![];
+                log_file.read_to_end(&mut data)?;
+                f.write_all(&data)?;
+                std::fs::remove_file(log_file_path)?;
+            }
+        }
+        return Ok(false);
+    }
+}
+
 fn main() {
     //file_path also can use '"target/logs/test.log"'
     fast_log::init(Config::new().chan_len(Some(100000)).console().file_split(
diff --git a/src/plugin/file_split.rs b/src/plugin/file_split.rs
index 8c75455..c6c9a6c 100644
--- a/src/plugin/file_split.rs
+++ b/src/plugin/file_split.rs
@@ -267,7 +267,10 @@ impl LogPack {
         if log_file_path.is_empty() {
             return Err(LogError::from("log_file_path.is_empty"));
         }
-        let log_file = OpenOptions::new().read(true).open(log_file_path);
+        let log_file = OpenOptions::new()
+            .write(true)
+            .read(true)
+            .open(log_file_path);
         if log_file.is_err() {
             return Err(LogError::from(format!(
                 "open(log_file_path={}) fail",
diff --git a/src/plugin/packer.rs b/src/plugin/packer.rs
index b8410df..052a100 100644
--- a/src/plugin/packer.rs
+++ b/src/plugin/packer.rs
@@ -1,8 +1,7 @@
 use crate::error::LogError;
 use crate::plugin::file_split::Packer;
-use std::fs::{File, OpenOptions};
-use std::io::{Read, Write};
-use std::path::Path;
+use std::fs::File;
+use std::io::Write;
 
 /// keep temp{date}.log
 #[derive(Clone)]
@@ -18,72 +17,6 @@ impl Packer for LogPacker {
     }
 }
 
-///pack by an date
-#[derive(Clone)]
-pub struct LogDatePacker {}
-
-impl LogDatePacker {
-    pub fn log_name_create_by_time(
-        &self,
-        first_file_path: &str,
-        date: fastdate::DateTime,
-    ) -> String {
-        let path = Path::new(first_file_path);
-        let file_name = path
-            .file_name()
-            .unwrap_or_default()
-            .to_str()
-            .unwrap_or_default()
-            .to_string();
-        let mut new_log_name = date.to_string().replace(" ", "T").replace(":", "-");
-        new_log_name.push_str(".");
-        new_log_name.push_str(self.pack_name());
-        new_log_name = first_file_path.trim_end_matches(&file_name).to_string() + &new_log_name;
-        return new_log_name;
-    }
-}
-impl Packer for LogDatePacker {
-    fn pack_name(&self) -> &'static str {
-        "log"
-    }
-
-    fn do_pack(&self, log_file: File, log_file_path: &str) -> Result<bool, LogError> {
-        //do nothing,and not remove file
-        let now = fastdate::DateTime::now()
-            .set_hour(0)
-            .set_min(0)
-            .set_sec(0)
-            .set_nano(0);
-        let name = self.log_name_create_by_time(log_file_path, now);
-        let mut f = OpenOptions::new()
-            .write(true)
-            .read(true)
-            .append(true)
-            .open(&name);
-        if let Ok(mut f) = f {
-            //append to file
-            let mut data = vec![];
-            if let Ok(mut old) = File::open(log_file_path) {
-                old.read_to_end(&mut data);
-                f.write_all(&data);
-                std::fs::remove_file(log_file_path);
-            }
-        } else {
-            //create file
-            f = OpenOptions::new().write(true).create(true).open(name);
-            if let Ok(mut f) = f {
-                let mut data = vec![];
-                if let Ok(mut old) = File::open(log_file_path) {
-                    old.read_to_end(&mut data);
-                    f.write_all(&data);
-                    std::fs::remove_file(log_file_path);
-                }
-            }
-        }
-        return Ok(false);
-    }
-}
-
 #[cfg(feature = "zip")]
 use zip::result::ZipResult;
 #[cfg(feature = "zip")]