fix renaming issue

README.md

@@ -7,12 +7,52 @@ Shrlok listens in the background on a Unix socket for a small header followed by
 data and pushes this data in a directory with some basic treatment. For example,
 text pushed to Shrlok is put into a `pre` tag of an HTML page.
 
-The current expected format is described at the top of the `shrlok.py` module.
 
-Supported types:
 
-- `txt`: put into a `pre` tag in an HTML page;
-- `raw`: put as is.
+Usage
+-----
 
-Example: TODO
+See the `share.sh` script to see how data can be sent to the socket from the
+shell.
 
+### Packet format
+
+The current expected format is described at the top of the `shrlok.py` module,
+but here is the short version:
+
+1. A packet length, as ASCII digits for convenience, ended with a null byte;
+2. A JSON header, ended with a null byte;
+3. Data.
+
+The packet length counts the JSON header, its null byte and the data length, not
+itself nor its own null byte terminator.
+
+The header must contain the key "type" with a supported type value.
+
+Example:
+
+``` python
+28\0{"type":"txt"}\0hello shrlok!
+```
+
+Supported types are:
+
+- `txt`: the data will be put in `pre` tags into an HTML page;
+- `raw`: the data will be written without modifications.
+
+### Header options
+
+| Key   | Value                                 | Supported by |
+|-------|---------------------------------------|--------------|
+| name  | file name (has precedence over `ext`) | raw          |
+| ext   | file extension                        | raw          |
+| title | Web page title                        | txt          |
+
+
+
+About
+-----
+
+I needed something to push stuff into the public folders of a Web server
+possibly from remote, and this is my own cute over-engineered solution that
+refuses to use TCP. Ask Kadaztrof what the name means because I don't know?

shrlok/shrlok.py

@@ -126,10 +126,10 @@ def write_content(data: bytes, name: str = "", extension: str = ""):
         os.chmod(output_file.name, 0o644)
         file_name = output_file.name
     if name:
-        new_file_name = os.path.join(os.path.dirname(file_name), name)
+        old_file_name = file_name
+        file_name = os.path.join(os.path.dirname(old_file_name), name)
         try:
-            os.rename(file_name, name)
-            file_name = new_file_name
+            os.rename(old_file_name, file_name)
         except OSError as exc:
             print(f"Failed to give required name to the file: {exc}")
             return None