copy file contents from the command line

I have a dotfiles repository where I store all of my settings for things like zsh and VS Code. Whenever I make a change to one of those files, I want to quickly copy them to update my repository.

There are a number of ways I can do this.

For example, I can use pbcopy to add the contents of a file to my clipboard and then paste them somewhere using cmd + v or pbpaste (assuming MacOS):

pbcopy < ~/.zshrc
pbpaste > ~/path/to/target/file.txt

(Note: The inverse, pbcopy, does not work, though cat ~/.zshrc | pbcopy does.)

Alternatively, I can merely redirect the contents from my .zshrc file to the respository’s equivalent:

cat ~/.zshrc | ~/code/dotfiles/.zshrc

These are yet more uses of redirection with the shell that I find very useful.