Add CODING-SYSTEM at the front of the priority list for automatic detection.
This also sets the following coding systems:
o coding system of a newly created buffer
o default coding system for subprocess I/O
This also sets the following values:
o default value used as `file-name-coding-system' for converting file names
o default value for the command `set-terminal-coding-system'
o default value for the command `set-keyboard-coding-system'
If CODING-SYSTEM specifies a certain type of EOL conversion, the coding
systems set by this function will use that type of EOL conversion.
A coding system that requires automatic detection of text+encoding
(e.g. undecided, unix) can't be preferred.
To prefer, for instance, utf-8, say the following: (prefer-coding-system 'utf-8)