I did this

Have ~/.netrc of:

macdef testmacro
	bin
	cd default
	cd login
	put login.bin
	cd ..
	cd password
	put password.bin
	quit

machine example.invalid
	login professor
	password joshua

curl -n http://example.invalid

NOTE: Use --resolve example.invalid:80:127.0.0.1 or similar to redirect the request to your test server.

Instead of using professor:joshua as credentials put:put is used instead.

I expected the following

netrc file parsing skipping macdef statements properly.

‘macdef name’

Define a macro. This token functions like the ftp macdef command functions. A macro is defined with the specified name; its contents begin with the next .netrc line and continue until a null line (consecutive new-line characters) is encountered. If a macro named init is defined, it is automatically executed as the last step in the auto-login process.

curl/libcurl version

curl 7.77.1-DEV (x86_64-pc-linux-gnu) libcurl/7.77.1-DEV OpenSSL/1.1.1k zlib/1.2.11 brotli/1.0.9 libidn2/2.3.0 libpsl/0.21.0 (+libidn2/2.3.0) libssh2/1.9.0 nghttp2/1.43.0 librtmp/2.3 OpenLDAP/2.4.57
Release-Date: [unreleased]
Protocols: dict file ftp ftps gopher gophers http https imap imaps ldap ldaps mqtt pop3 pop3s rtmp rtsp scp sftp smb smbs smtp smtps telnet tftp
Features: alt-svc AsynchDNS brotli HSTS HTTP2 HTTPS-proxy IDN IPv6 Largefile libz NTLM NTLM_WB PSL SSL TLS-SRP UnixSockets

operating system

Linux hostname 5.10.0-6-amd64 #1 SMP Debian 5.10.28-1 (2021-04-09) x86_64 GNU/Linux