[CC updated] Hi folks,
This thread started on the groff@gnu list, so I'm looping it back in. https://lists.gnu.org/archive/html/groff/2025-02/msg00088.html https://lists.gnu.org/archive/html/groff/2025-03/msg00070.html The formatter, GNU troff: * catenates its input into a single stream, disregarding any file "boundaries" except the first and the last; * does not generally require the input to end with a newline; * throws a warning diagnostic if the input ends with the *roff escape character (and ignores that character); * warns about and discards NUL characters from the input (along with several others that are invalid as input); * always terminates its _output_ files (whether in Kernighan's "trout" format [originally seen in CSTR #97], or "approximate" [`troff -a`] format) with newlines (ASCII LF); * and writes only printable ASCII characters and the space in "trout"/"grout" or approximate outputs, with one esoteric exception.[1] I'd like to know what, specifically, this program should be doing differently. Regards, Branden [1] The `cf` request permits the copying of abritrary bytes from the input file named by it to "grout" output. In the forthcoming _groff_ 1.24.0, the formatter handles this request only in the non-default "unsafe mode" enabled by the `-U` command-line option. Quoting groff's Texinfo manual: -- Request: .trf ["]file -- Request: .cf ["]file Copy FILE as "throughput" to GNU 'troff' output. Each line of FILE is output as if preceded by '\!', but is not interpreted by the formatter. If FILE does not end with a newline, 'trf' appends one. Both requests break the line before reading FILE, unless invoked with the no-break control character. When used in a diversion, these requests embed a node (*note Gtroff Internals::) in it that, when interpolated, causes the contents of FILE to be copied to the output. In AT&T 'troff', 'cf' does so even if a diversion is in use; this behavior is so anomalous that it must be considered a bug. 'cf' copies the contents of FILE completely unprocessed; it is therefore an error to use this request in safer mode, which is the default. Invoke GNU 'troff' or a front end with the '-U' option to enable unsafe mode. 'trf' discards invalid input characters; recall *note Identifiers::. For 'cf', within a diversion, "completely unprocessed" means that each line of a file to be inserted is handled as if it were preceded by '\!\\!'. *Caution:* Use of these requests can put syntactically invalid content into the formatter's output, which 'groff''s output drivers then fail to process. One application is to pass instructions to a postprocessor that interprets FILE's contents and filters it out before sending it to the output device.
signature.asc
Description: PGP signature
