Need a clarification on tcp-echo-server example

[RealYukiSan]

I'm sorry if this question sounds like a dumb question, but I'll ask it anyway.

Why isn't the req variable, which is allocated dynamically using malloc, freed within the echo_read function? I notice that only buf->base is being freed in the function.

Will this function be safe from memory leaks? Is it acceptable to not free variables allocated by malloc?

here's the snippet code that I'm talking about:

void echo_read(uv_stream_t *client, ssize_t nread, const uv_buf_t *buf) {
    if (nread > 0) {
        write_req_t *req = (write_req_t*) malloc(sizeof(write_req_t));
        req->buf = uv_buf_init(buf->base, nread);
        uv_write((uv_write_t*) req, client, &req->buf, 1, echo_write);
        return;
    }
    if (nread < 0) {
        if (nread != UV_EOF)
            fprintf(stderr, "Read error %s\n", uv_err_name(nread));
        uv_close((uv_handle_t*) client, on_close);
    }

    free(buf->base);
}

[bnoordhuis]

It's freed in echo_write. The uv_write_t needs to persist until that function is called.

[RealYukiSan]

thanks for the answers!
By the way, would you be willing to address my other question as well?