Question

I have been using zsh globbing for commands such as:

 vim **/filename
 vim *.html.erb

and so on, but when I type in something like:

 find . -name *mobile*

I get the response:

 zsh: no matches found: *mobile*

Why?

Answer 1

find . -name *mobile* # does not work

vs

find . -name '*mobile*' # works

The difference is due to the steps that the shell takes when it parses a line. Normally, the shell expands any wildcards it finds before it runs the command. However, the single quotes mark the argument as being a literal, which means that the shell does not perform wildcard expansion on that argument before running the command.

To demonstrate the difference, suppose you are in a directory with the following files:

$ tree
./
mobile.1
dir/
    mobile.2

In the first case, without single quotes, zsh will process as follows:

• expand the glob, rendering simply mobile.1 (because that is the only matching filename in the current directory
• pass the result to find, hence:

find . -name mobile.1

So find will only look for files named literally mobile.1

In the second form, with single quotes, the entire glob will be preserved and passed to find:

find . -name *mobile*

Which means that find will look for any filename containing the string "mobile".

The important thing to note here is that both zsh and find support the same wildcard syntax; by using single quotes, you induce find to handle the wildcards in this case rather than zsh.