“human readable” sizes with ls -sh on FreeBSD

Question

With GNU ls one can get "human readable" file sizes (this means suffixes like K, M, G, ... for Kilo-, Mega- and Gigabyte etc. are appended and the number is kept below 1024) with the option -h even if not used in conjunction with -l but only with -s.

How can one get this behavior with the ls that comes with FreeBSD, i.e. how does one get ls -sh to work in FreeBSD?

AFAIK, GNU ls does not output "human readable" sizes without -h. — Kusalananda, Aug 10 '16 at 11:36
it does, with ls -sh. The manual says h, --human-readable: with -l and/or -s, print human readable sizes (e.g., 1K 234M 2G) — ilkkachu, Aug 10 '16 at 11:40
But the ls on my OS X doesn't support that combination. Don't know about FreeBSD. (Obvious workaround: install GNU ls) — ilkkachu, Aug 10 '16 at 11:41
@ilkkachu: the manual says -h When used with the -l option, use unit suffixes. It does not work out of the box in FreeBSD. — viuser, Aug 10 '16 at 11:43
I just tried all I said, and it worked (in both default csh and in bash). If you say what version of FreeBSD and which login shell you are using, we will help. — , Aug 10 '16 at 12:11
A plain ls -h doesn't display any size whatsoever. Only ls -s and ls -l display sizes. — Gilles 'SO- stop being evil', Aug 10 '16 at 23:06

score 4 · Answer 1 · answered Aug 11 '16 at 00:03

The way to answer this is to read the source code:

FreeBSD ls uses the -h option in a couple of places. It does this first when it needs statistics for a file.
It needs statistics when doing a "longform" (-l), inode (-i) or size (-s) option, to compute the width of the largest number.
If none of those options are set, it doesn't use the -h option.
It combines the -h with -i and/or -s when doing a long listing (-l), specifically when it prints sizes. Otherwise, it is ignored.

No error is reported if -h is given without any of those options.

FreeBSD added the option in 2001, well before the (rather old) userland in OSX. The FreeBSD and OSX manual pages have identical descriptions of -h (and "ls -lh" works for both). But at that point, it only worked with -l:

Add a new flag, -h which when combined with the -l option causes file sizes to be displayed with unit suffixes; Byte, Kilobyte, Megabyte, Gigabyte, Terabyte and Petabyte in order to reduce the number of digits to three or less.

score 0 · Answer 2 · edited Apr 13 '17 at 12:36

If you want GNU ls features on FreeBSd, you can install the gnuls package and alias ls to gnuls.

If you want to stick to the base software, you can post-process the output of ls. (Script reposted from how do you sort du output by size?) This works on any POSIX system.

CLICOLOR_FORCE=1 ls | awk '
    function human(x) {
        s="kMGTEPYZ";
        while (x>=1000 && length(s)>1)
            {x/=1024; s=substr(s,2)}
        return int(x+0.5) substr(s,1,1)
    }
    {gsub(/^[0-9]+/, human($1)); print}'

CLICOLOR_FORCE causes BSD ls to use colors even if it isn't writing to a terminal. On the other hand, because ls isn't writing to a terminal, you'll get one file per line instead of columns. On FreeBSD, you can use the option -C to get columns, but then the postprocessing script becomes a lot more complex since it needs to find sizes in the middle of the line. Try this (untested):

CLICOLOR_FORCE=1 ls -C | awk '
    function human(x) {
        s="kMGTEPYZ";
        while (x>=1000 && length(s)>1)
            {x/=1024; s=substr(s,2)}
        return int(x+0.5) substr(s,1,1)
    }
    {gsub(/(^|  )[0-9]+/, human($1)); print}'

“human readable” sizes with ls -sh on FreeBSD

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