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Diff files


This article is about the text difference file format. For the binary patches mainly used for client modification, see Hexing.

A diff file is a file to make:

  • implementation of a modification easier
  • check what and where you modified things
  • share your modifications with the rest of the world
  • it is also an easy way for people that give support on forums to check themselves what is wrong to the modifications you made

Creating .diff files using the tortoise menu

  1. right click on the folder
  2. goto TortoiseSVN menu
  3. click create patch
  4. save as .diff file

Manually Creating .diff files (knowing the mechanics and repairing .diffs if needed)

  1. create a new txt file
  2. rename the .txt extention to .diff
  3. start with pointing out the index (path where the diff files will patch)
    • src
  4. add a ========================================= line to indicate the next file
    • example: =========================================
  5. add the patch of the file where content will be removed (---) and add the revision
    • example:---> src/common/mmo.c (revision 12300 Stable)
  6. add the path of the file where content will be added (+++) and add (working copy)
    • example:+++> src/common/mmo.c (working copy)
  7. add the location of the lines that need to be modified in this way:
    -100: start reading original lines at line 100
    ,5: read 5 original lines
    +100: start reading new lines at line 100
    ,7: read 7 new lines
  8. add a space and write a line that is from the original text (this line will be unmodified) and all others starting with a space
    • example: <space>this line will be unmodified
  9. add a - and write the line that must be modified
    • example: -line will be removed from the original code
  10. add a + and write the line that need to be placed to replace or added to the original code
    • example: +this line will be added in the new code
    • full example on a @@ -x,7 +x,8 @@:[code]line1: this line will be unmodified

line2: this line will be unmodified line3:-this line will be deleted line4:+this line will replace line 3 line5:+this line will add a line of code line6: this line will be unmodified, but will move down one line line7: line8: this line will be unmodified, move down one line (same as the line above since an counts as a line)[/code]

#**[color=red]NOTICE= THE ON LINE 7 MUST START WITH A as well[/color]

Using .diff/.patch files to patch your server


  1. go place the folder in the index folder
  2. richt click the *.diff file and go to TortoiseSVN menu
  3. click patch


cd /path/to/your/server/folder
patch -p0 < /path/to/patch/file/filename.extension

Example of a .diff file

Index: map/clif.c  
--- map/clif.c	(revision 13318)  
+++ map/clif.c	(working copy)  
@@ -6745,7 +6745,7 @@  
 	 * Marry [DracoRPG]  
-	void clif_marriage_process(struct map_session_data *sd)  
+	/*void clif_marriage_process(struct map_session_data *sd)  
 		int fd;  
@@ -6755,8 +6755,8 @@  
+	*/  
	  * Notice of divorce  
Index: map/clif.h  
--- map/clif.h	(revision 13318)  
+++ map/clif.h	(working copy)  
@@ -53,8 +53,8 @@  
	 // packet DB  
-#define MAX_PACKET_DB		0x400  
-#define MAX_PACKET_VER		22  
+#define MAX_PACKET_DB		0x500  
+#define MAX_PACKET_VER		23  
	 struct s_packet_db {  
	 	short len;

See Also

Category:File Formats