How does Apple's "find -regex" work?

Question

I'm trying to create a -regex expression for find on macOS.

find /Users/gerben/Library -regex '.*\(cisco\).*' -print 2>/dev/null

works, and so does

find /Users/gerben/Library -regex '.*\(citrix\).*' -print 2>/dev/null

in the sense that they both find files. Now I try

find /Users/gerben/Library -regex '.*\(cisco|citrix\).*' -print 2>/dev/null

and nothing is found. Nor does

find /Users/gerben/Library -regex '.*\(cisco\|citrix\).*' -print 2>/dev/null

nor any other variation with {} escapes and what not that I have tried. What am I doing wrong?

Answer 1

You can use -E flag, from man:

-E Interpret regular expressions followed by -regex and -iregex primaries as extended (modern) regular expressions rather than basic regular expressions (BRE's). The re_format(7) manual page fully describes both formats.

In this case your find command will look like:

find -E ~/Library -regex '.*(citrix|cisco).*' -print 2>/dev/null