TAIL(1plan9)

🌸 TAIL — the last-part-of-a-file delivery service 💅

okay bestie, this is tail from the Plan 9 manual, section 1. she delivers the last part of a file. that's the whole job. she's an icon, she's efficient, she eats. ✨

✨ SYNOPSIS ✨

tail [ +-number[lbc][rf] ] [ file ]

tail [ -fr ] [ -n nlines ] [ -c nbytes ] [ file ]

two whole ways to summon her. pick your fighter. 🫶

💖 DESCRIPTION 💖

okay so. tail copies the named file over to the standard output, starting from a designated place. no file named? then she just copies the standard input instead. lowkey flexible of her.

copying begins at position +number measured from the beginning, or -number from the end of the input. and number is counted in lines, 1K blocks, or bytes, according to the appended flag — l, b, or c. and if you don't say? the default is -10l (ten ell, as in ten lines, bestie).

the r flag? she prints lines from the end of the file in reverse order. dramatic. love that for her. and f (follow) means that after she's done printing to the end, she keeps watch and prints further data as it appears. she is not leaving. she's staying. main character energy fr fr. 👑

and the second syntax up there is the one POSIX put out into the world, where the numbers — not the options — are the ones that are signed. iykyk. 💀

🌈 EXAMPLES 🌈

• tail file — print the last 10 lines of a file. simple. iconic.
• tail +0f file — print a file, and keep watching data accumulate as it grows. she's glued to it. obsessed.
• sed 10q file — print the first 10 lines of a file. yes this is a different tool, yes she's still slaying, no we're not gatekeeping. 💜

🎀 SOURCE 🎀

/src/cmd/tail.c

that's where she lives. that's her address. don't be weird about it. 🏠

💀 BUGS 💀

heads up babes, there are some things you gotta know.

• tails relative to the end of the file are treasured up in a buffer, and thus are limited in length. so if your file is huge and you're asking for the tail end of it, she can only hold so much. 😭
• according to custom, the option +number counts lines from 1, and counts blocks and bytes from 0. yes it's inconsistent. yes it's tradition. we don't make the rules. 🙈
• tail is ignorant of UTF. she does not know her unicode. she does not see the characters. she simply counts. do with that information what you will. 🦋

okay that's the whole page!! this was TAIL(1plan9) from the Plan 9 manual — go forth and read the ends of files responsibly, bestie. mwah. 💖✨🎀