LOWDOWN_NROFF_NEW(3) Library Functions Manual LOWDOWN_NROFF_NEW(3)

lowdown_nroff_newallocate a roff renderer for lowdown documents

library “liblowdown”

#include <sys/queue.h>
#include <stdio.h>
#include <lowdown.h>

void *
lowdown_nroff_new(const struct lowdown_opts *opts);

Allocates a roff renderer using opts->oflags and opts->type, or zero and LOWDODN_NROFF, respectively, if opts is NULL. These are documented in lowdown(3). The returned pointer may be used with multiple invocations of lowdown_nroff_rndr(3) and must be freed with lowdown_nroff_free(3).

The bits recognised in opts->oflags are LOWDOWN_NROFF_GROFF, LOWDOWN_NROFF_NOLINK, LOWDOWN_NROFF_NUMBERED, LOWDOWN_NROFF_SHORTLINK, LOWDOWN_NROFF_SKIP_HTML, and LOWDOWN_STANDALONE.

The values recognised in opts->type are LOWDOWN_MAN and LOWDODN_NROFF: anything else triggers LOWDODN_NROFF.

If LOWDOWN_NROFF_GROFF is set in LOWDOWN_MAN mode, macros from the man-ext package as well as the original man are used in output. These are supported by both groff and mandoc. If in LOWDODN_NROFF mode, GNU extensions to ms are used along with mspdf. These are only supported by groff.

Returns a pointer to the renderer or NULL on memory failure. The returned pointer must be freed with lowdown_nroff_free(3).

The following assumes the the string buf of length bsz consists of Markdown content.

struct lowdown_buf *out;
struct lowdown_doc *doc;
struct lowdown_node *n;
void *rndr;

if ((doc = lowdown_doc_new(NULL)) == NULL)
  err(1, NULL);
if ((n = lowdown_doc_parse(doc, NULL, buf, bsz)) == NULL)
  err(1, NULL);
if ((out = lowdown_buf_new(256)) == NULL)
  err(1, NULL);
if ((rndr = lowdown_nroff_new(NULL)) == NULL)
  err(1, NULL);
if (!lowdown_nroff_rndr(out, NULL, rndr, n))
  err(1, NULL);

fwrite(out->data, 1, out->size, stdout);

lowdown_nroff_free(rndr);
lowdown_buf_free(out);
lowdown_node_free(n);
lowdown_doc_free(doc);

lowdown(3), lowdown_nroff_free(3), lowdown_nroff_rndr(3),

This uses both the original troff man macros for Version 7 AT&T UNIX, defined in man(7), and the man-ext groff extensions. Both are implemented in mandoc.

The troff ms macros are defined in groff_ms(7), with the mspdf groff extensions described in "Portable Document Format Publishing with GNU Troff" by Keith Marshall. Neither are implemented in mandoc.

March 28, 2021 OpenBSD 6.7