What's the + in find /path/ -exec command '{}' + do?

Question

What's the + in find /path/ -exec command '{}' + do? as opposed to find /path/ -exec command '{}' \;

Answer 1

The '+' makes one big command line out of all found files to minimize the number of commands to be run.

Given the case that a find command finds four files.

find . -type f -exec command '{}' \;

would produce

command file1
command file2
command file3
command file4 

On the other hand

find . -type f -exec command '{}' \+

produces

command file1 file2 file3 file4

Answer 2

From the man page:

-exec command {} +

This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command. The command is executed in the starting directory.