Autoexec

Autoexec is a CFG file for launching a game with set convars that will get automatically executed on launch.

To create an autoexec create a text document named 'autoexec' and save it with a .cfg extension, then place it inside:

For GoldSrc: Your game / mod's "moddir" folder, example: Half-Life/valve/autoexec.cfg
For Source: Your game / mod's "cfg" folder, example: Half-Life 2/hl2/cfg/autoexec.cfg

Place all the convars inside the file with each convar on a seperate line. For example:

cl_showfps 1
maxplayers 1
sv_cheats 1

Note:

Explain the operation in more detail.
* Server execute ...cfg/autoexec.cfg file once, on server startup, before first map is loaded.
* From this config file, you can use console variables which would not work while map is loaded or it require map change.
  - For one example, sv_pure is one of those. This cvar require map change when setting change.
--------------------------------------------------------
sv_pure set to 0.
Note: Waiting for the next changelevel to apply the current value.
--------------------------------------------------------
  - Problem is, if there are players on server, before sv_pure setting take effect, players are going to experience lot of bugs and glitch on next map.
    So, change sv_pure from ...cfg/autoexec.cfg or from launch parameter: +sv_pure 1