Linux tips: making a patch, core dump file

Tip 1: making a patch

To create a patch:
   $ diff -u original-file updated-file > patch-file

To appliy a patch:
   $ patch original-file patch-file


Tip 2: enable core dump file

In some system, core dump file can not be generated by default. When you run command
   $ ulimit -a
or
   $ ulimit -c

You can see your max core file size is set as 0, which prevent a dumping of the core file. To enable core dump, you will want to run
   $ ulimit -c unlimited

to allow core files to be generated.