MODBUS_CLOSE(3)

💖 MODBUS_CLOSE 💖

okay bestie, gather round, because today we're learning how to say bye to a Modbus connection the polite way 🎀 this one lives in the libmodbus Manual, and it is genuinely the easiest page in the whole library. no cap. it's giving "one job, done perfectly" energy 👑

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🌸 NAME 🌸

modbus_close — close a Modbus connection

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✨ SYNOPSIS ✨

void modbus_close(modbus_t *ctx);

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🦋 DESCRIPTION 🦋

so like. the modbus_close() function shall close the connection that was established with the backend set in the context. that's it. that's the whole vibe. you connected, you did your thing, now you're closing the door behind you like the main character you are 💅

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💜 RETURN VALUE 💜

there is no return value. none. zero. nada. it's a void function, she doesn't gossip back to you, she just does 🫶

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🌈 EXAMPLE 🌈

here's the whole glow-up arc in code form, bestie — connect, check, close, free, periodt:

    modbus_t *ctx;

    ctx = modbus_new_tcp("127.0.0.1", 502);
    if (modbus_connect(ctx) == -1) {
        fprintf(stderr, "Connection failed: %s\n", modbus_strerror(errno));
        modbus_free(ctx);
        return -1;
    }

    modbus_close(ctx);
    modbus_free(ctx);

see how she closes ctx and then frees it? iconic behavior. do not skip steps 🍓

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👑 SEE ALSO 👑

• modbus_connect(3)

(the prequel to this masterpiece, fr fr)

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💖 AUTHORS 💖

the libmodbus documentation was written by Stéphane Raimbault <stephane.raimbault@gmail.com> — absolute legend, we stan a documentation king 👑

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ok that's the whole page, you're officially a modbus_close expert now, no notes 💀✨

and for the credits roll at the very end: this lil beauty is libmodbus v3.1.6, dated 11/17/2025. slay, bye bestie!! 🎀🦋💜