How to start emacs in "nothing" mode (`fundamental-mode`)

Question

If I type emacs test.sh Emacs insists on putting me in Shell-script mode. Another time I want to edit the file help.txt and then Emacs puts me in Text mode. But sometimes I don't want any of this, especially when I am doing a large paste into Emacs from some other source.

How do I start Emacs in "nothing" mode? No special indenting, spacing, etc., and Emacs simply takes the characters in as they are entered.

UPDATE: Here is an example. Copy the following text to your clipboard, open emacs (even in fundamental mode) and paste.

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<EntityDescriptor xmlns="urn:oasis:names:tc:SAML:2.0:metadata"
xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
xmlns:shibmd="urn:mace:shibboleth:metadata:1.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 ID="FARM20190311T2248"
 Name="https://www.example.com/"
 entityID="https://www.example.com/" validUntil="2020-03-11T22:48:12Z"><ds:Signature>
<ds:SignedInfo>
<ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>

Emacs insists on changing the spacing (even in fundamental mode and using -q) to this:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<EntityDescriptor xmlns="urn:oasis:names:tc:SAML:2.0:metadata"
xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
xmlns:shibmd="urn:mace:shibboleth:metadata:1.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 ID="FARM20190311T2248"
  Name="https://www.example.com/"
   entityID="https://www.example.com/" validUntil="2020-03-11T22:48:12Z"><ds:Signature>
   <ds:SignedInfo>
   <ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>

Try the same experiment with vi or nano. Those programs (at least on my computer) do not change the spacing.

I am using GNU Emacs 24.5.1 on Debian stretch.

Answer 1

When you use M-x find-file-literally Emacs will not invoke a mode that is based on the file name. Instead, it uses fundamental-mode as the major mode.

From the command line you can use something like this:

emacs --eval '(find-file-literally "yourfile.ext")'

Answer 2

Emacs modes are established for each file you open, so opening Emacs in "nothing mode" doesn't necessarily accomplish what you're after. Each file you open after starting Emacs will get its own mode applied.

You can use the command @clemera provides to open a file in fundamental mode from the command line. You can do the same from an already-running Emacs via M-x find-file-literally. You can "turn-off" the major mode for a file you've already opened by selecting fundamental mode (which is basically "nothing mode"): M-x fundamental-mode

Answer 3

I'm running:
GNU Emacs 25.2.2 (x86_64-pc-linux-gnu, GTK+ Version 3.22.30) of 2018-08-26, modified by Debian

$ emacs yourfile.txt --eval '(fundamental-mode)'

You have to put the --eval after the file name or it appears to set the mode based on the file name.