Date: Tue, 19 Jun 2018 21:34:09 -0400 From: Farhan Khan <khanzf@gmail.com> To: freebsd-hackers@freebsd.org Subject: Re: Printing UTF-8 characters Message-ID: <CAFd4kYAY-80U2hJHYw_-OBKwcjQnNgN19%2BjP1tu%2BF939aL6bZw@mail.gmail.com> In-Reply-To: <20180202035130.C51F8156E80B@mail.bitblocks.com> References: <CAFd4kYD_Q9Y84LvCGELVodt%2B30KM_KzNzoLOzudZm9kaLqGPaQ@mail.gmail.com> <20180201072831.GA2239@c720-r314251> <CAFd4kYB_eU00Z5nBzp-iNGuELN4cy_ADGABb-boq4Fvn-a0XMg@mail.gmail.com> <20180202035130.C51F8156E80B@mail.bitblocks.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, Feb 1, 2018 at 10:51 PM, Bakul Shah <bakul@bitblocks.com> wrote: > On Thu, 01 Feb 2018 10:42:36 -0500 Farhan Khan <khanzf@gmail.com> wrote: >> Sorry, that was a poorly phrased question on my part. Let me try again. >> I am trying to make text align in columns in a terminal. My >> understanding is that characters above 0x7E are 3 bytes in length. A >> modern terminal will render that as either a single question-mark or >> the character itself, making terminal column alignment easy. But how >> would an older terminal display a 3-byte character? I am worried that >> would render as 3 question marks and throw off column alignment. If >> so, is there a proper way to perform alignment for both newer and >> older terminals? > > UTF-8 can use upto 4 bytes to encode a unicode point, > depending on the script. > > For what you want, you can use openoffice like programs that > understand unicode and can do complex text layout. Normal > terminal programs typically use monospace (fixed width) fonts > are simply not capable of what you want. The assumption that > one char means one rectangular cell on the screen is too > deeply woven in them. Particularly for Indic languages this > just doesn't work, You may have N unicode points, each of > which require 3 bytes, all together map to a one single glyph. Hi all, To follow-up from my earlier poorly asked question from a few months back, how do I determine if the terminal is capable of printing UTF-8 encoded strings and/or unicode in general? The obvious answer is to check the LANG variable via getenv(3), but what if you are using "en_US.UTF-8" vs "en_GB.UTF-8"? Should I just check for the string "UTF-8" in the LANG variable? My concern is printing characters above 0x7F on terminals/encodings that are not capable of displaying them, resulting in unusual behavior. Thanks, -- Farhan Khan PGP Fingerprint: B28D 2726 E2BC A97E 3854 5ABE 9A9F 00BC D525 16EE
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAFd4kYAY-80U2hJHYw_-OBKwcjQnNgN19%2BjP1tu%2BF939aL6bZw>