NNG_URL_PARSE(3)

💖 NNG_URL_PARSE 💖

okay bestie, so this is the NNG Reference Manual page for nng_url_parse and honestly? it's a whole personality. it takes a URL string and hands you back a struct. iconic behavior. let's get into it 🫶

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✨ NAME ✨

nng_url_parse — create URL structure from a string

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🌸 SYNOPSIS 🌸

#include <nng/nng.h>

int nng_url_parse(nng_url **urlp, const char *str);

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🦋 DESCRIPTION 🦋

so nng_url_parse() does the thing: it parses the string str, which is supposed to contain an URL that's compliant with RFC 3986 (https://tools.ietf.org/html/rfc3986), and it builds you a fresh nng_url structure holding all the results. a pointer to that shiny new structure gets stashed in urlp. 💅

and when you're done with the structure? you can absolutely dispose of it whenever it's no longer needed, by calling nng_url_free(). clean up after yourself, queen. 🎀

🧚 URL Canonicalization

not only does it parse, it also canonicalizes the results, and here's literally every step it does, no skips:

1. The URL is parsed into the various components.
2. The u_scheme, u_hostname, u_host, and u_port members are converted to lower case.
3. Percent-encoded values for unreserved characters (https://tools.ietf.org/html/rfc3986#section-2.3) converted to their unencoded forms.
4. Additionally URL percent-encoded values for characters in the path and with numeric values larger than 127 (i.e. not ASCII) are decoded.
5. The resulting u_path is checked for invalid UTF-8 sequences, consisting of surrogate pairs, illegal byte sequences, or overlong encodings. If this check fails, then the entire URL is considered invalid, and the function returns NNG_EINVAL.
6. Path segments consisting of . and .. are resolved as per RFC 3986 6.2.2.3 (https://tools.ietf.org/html/rfc3986#section-6.2.2.3).
7. Further, empty path segments are removed, meaning that duplicate slash (/) separators are removed from the path.
8. If a port was not specified, but the scheme defines a default port, then u_port will be filled in with the value of the default port.

💡 Tip Only the u_userinfo, u_query, and u_fragment members will ever be NULL. The other members will be filled in with either default values or the empty string if they cannot be determined from str.

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🌈 RETURN VALUES 🌈

This function returns 0 on success, and non-zero otherwise. slay when it's zero, sad vibes when it's not 😭

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💀 ERRORS 💀

• NNG_ENOMEM — Insufficient free memory exists to allocate a message.
• NNG_EINVAL — An invalid URL was supplied.

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👑 SEE ALSO 👑

nng_url_clone(3), nng_url_free(3), nng_strerror(3), nng_url(5), nng(7)

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and that's the whole page, bestie 💜 this one's from the NNG Reference Manual, dated 2026-06-30. go forth and parse those URLs responsibly ✨🦋🌸