# and ; meaning in Linux.

[gardenair]

hi,
In any configuration file if we want to comment that particular line Linux allow " # " sign. Where as there is another character " ; " which is also use in configuration files like in smb.conf

I shall be glad if you may guide me what " ; " function of this character is ?

Thanks.

[Xian]

When the option is commented with ";" it means the setting differs from the default program behavior.

[gardenair]

well it is just like comments.The system not read that line when it execute
Example /etc/network/interfaces

# This ia a test line for assigning IP Address.
; address 192.168.1.10
; netmask 255.255.255.0
; gateway  192.168.1.1

The Linux kernel will not read both line if it is inside the configuration file.If I um-comment " ; " thing works.

So what is the difference in # and ;

[guiverc]

Which standard to use.... https://xkcd.com/927/

GNU options are usually '--' in front of the option, unix tends to use '-' (or nothing; `ps aux`)
GNU/Linux tends to use "#" as marking comments; BSD tends to prefer ";"

But our systems today are a mixture of some components that started up the older BSD or unix world; plus other parts that were from GNU or Linux, thus some programs/applications use the ";" whilst others use "#" etc

The difference is where the programmer initially came from; which "standard" or OS the developer preferred... and thus which he/she then implemented in their newer created project/application.

The difference is just historical & which standard felt "most at home" to the developer.

I'll refer back to the XKCD comic - https://xkcd.com/927/

[Geoff_Lane]

When the option is commented with ";" it means the setting differs from the default program behavior.

Ah, interesting. Didn't actually know that.

geoff

[Xian]

The OP referenced a specific file as an example of their question.

In that file the following is shown below.

It's use with that application is not expected to be found globally.

# Some options that are often worth tuning have been included as# commented-out examples in this file.
#  - When such options are commented with ";", the proposed setting
#    differs from the default Samba behaviour
#  - When commented with "#", the proposed setting is the default
#    behaviour of Samba but the option is considered important
#    enough to be mentioned here

[gardenair]

Thanks a lot for the valuable information. In short we can say that " # " or " ; " have same characteristics .

[The Cog]

Thanks a lot for the valuable information. In short we can say that " # " or " ; " have same characteristics .

That's not at all universally true. Many configuration files use just one or the other. I think that being able to use either in a configuration file is unusual.

[mIk3_08]

For me;
The ";" this is to declare a function to be functional. sensitive type of function.
while "#" this is to avoid the string to be functional in short non-functional
That is in my opinion.
But in IRC this "#" can be a channel #ubuntu