ngx_output_chain  163 src/core/ngx_buf.h ngx_int_t ngx_output_chain(ngx_output_chain_ctx_t *ctx, ngx_chain_t *in);
ngx_output_chain  152 src/http/ngx_http_copy_filter_module.c     rc = ngx_output_chain(ctx, in);
ngx_output_chain 1868 src/http/ngx_http_upstream.c        return ngx_output_chain(&u->output, out);
ngx_output_chain 1909 src/http/ngx_http_upstream.c             rc = ngx_output_chain(&u->output, out);