What does this error msg means?

help
1 
error: failed to parse manifest at `/home/user_saksham/opt/rust/projects/rust_os/Cargo.toml`

Caused by:
  this virtual manifest specifies a `bin` section, which is not allowed

Testing | Writing an OS in Rust am following this tutorial and seem to be lost.Can anyone help me with this?

2

The error indicates that you have tried to add a bin section to a Cargo.toml that doesn't have a package section. It's difficult to tell exactly why that has happened without seeing your code, but the Cargo.toml example in the page you linked to is intended to be added to the existing Cargo.toml from the previous parts. In particular, the cargo new command near the start of the first post should generate a valid package section.

3

The tutorial assumes you created Cargo.toml using cargo new or cargo init. The [[bin]] section is not the whole file, it must be added to an existing package specification.

Run cargo init inside an empty directory to get a usable Cargo.toml template.