Re: Possibly Off Topic Rant

[Ray Parrish]

Chet Ramey wrote:
> Ray Parrish wrote:
>   
> > Hello,
> >
> > I'm a fairly new user in Linux, and I've been studying and attempting to
> > use the commands available to me at the command line by reading the man
> > and info pages. I'm running into lots of problems determining the proper
> > syntax for many of the commands due to very sketchy documentation.
> >
> > I'm winding up trying some commands over and over again, as I attempt to
> > discover the apparently secret twists to the syntax required to get a
> > command to do it's thing. After many tries I sometimes finally get it
> > right, and there is no mention in the docs of the requirement for the
> > use of specific syntax options I eventually discover are required to use
> > a command.
> >
> > I consider this a bug in the documentation, and think it would be nice
> > if the documentation writers would add a --verbose --verbose switch to
> > their writing behaviors when producing man pages.
> >     
>
> There are literally hundreds of books available on Unix use, programming,
> and shell scripting.  They fill this niche, not manual pages.
>
> Chet
>   
Granted, and I've installed quite a few of them from the repositories,
but it would be nice if the man pages would at least mention things like
"this parameter has to be quoted to work" or use a * on the end of the
path to activate the --recursive option. It took me hours to find that
out with the ls command, see following output. -

ray@ray-desktop:~$ ls --recursive -d /proc/
/proc/
ray@ray-desktop:~$ ls --recursive -d /proc/*
/proc/1 /proc/4 /proc/8973 /proc/9826 /proc/fs
/proc/10012 /proc/41 /proc/8976 /proc/9828 /proc/interrupts
/proc/10018 /proc/44 /proc/8979 /proc/9829 /proc/iomem
/proc/10023 /proc/45 /proc/9041 /proc/9833 /proc/ioports
/proc/10025 /proc/4521 /proc/9059 /proc/9860 /proc/irq
/proc/10027 /proc/5 /proc/9060 /proc/9889 /proc/kallsyms
/proc/10029 /proc/5867 /proc/9083 /proc/9891 /proc/kcore
/proc/10050 /proc/6 /proc/9084 /proc/9897 /proc/key-users
/proc/10058 /proc/6101 /proc/9093 /proc/9902 /proc/kmsg
/proc/10060 /proc/6149 /proc/9105 /proc/9911 /proc/loadavg
/proc/10063 /proc/6190 /proc/9109 /proc/9916 /proc/locks
/proc/10066 /proc/6239 /proc/9203 /proc/9917 /proc/meminfo
/proc/10069 /proc/6254 /proc/9209 /proc/9921 /proc/misc
/proc/10077 /proc/7 /proc/9211 /proc/9922 /proc/modules
/proc/10083 /proc/7032 /proc/9213 /proc/9923 /proc/mounts
/proc/10106 /proc/7033 /proc/9224 /proc/9929 /proc/mtrr
/proc/10110 /proc/7037 /proc/9261 /proc/9957 /proc/net
/proc/10122 /proc/7038 /proc/9269 /proc/9960 /proc/pagetypeinfo
/proc/10126 /proc/7040 /proc/9272 /proc/9966 /proc/partitions
/proc/10159 /proc/7151 /proc/9273 /proc/9969 /proc/sched_debug
/proc/10207 /proc/7191 /proc/9282 /proc/9972 /proc/scsi
/proc/164 /proc/7270 /proc/9290 /proc/9975 /proc/self
/proc/1826 /proc/7338 /proc/9297 /proc/9978 /proc/slabinfo
/proc/1829 /proc/7340 /proc/9339 /proc/9995 /proc/stat
/proc/1843 /proc/7374 /proc/9342 /proc/acpi /proc/swaps
/proc/1849 /proc/7402 /proc/9346 /proc/asound /proc/sys
/proc/2 /proc/7416 /proc/9502 /proc/buddyinfo /proc/sysrq-trigger
/proc/203 /proc/7429 /proc/9530 /proc/bus /proc/sysvipc
/proc/204 /proc/7449 /proc/9680 /proc/cgroups /proc/timer_list
/proc/2408 /proc/7450 /proc/9684 /proc/cmdline /proc/timer_stats
/proc/2412 /proc/7479 /proc/9719 /proc/cpuinfo /proc/tty
/proc/245 /proc/7754 /proc/9776 /proc/crypto /proc/uptime
/proc/2679 /proc/7874 /proc/9790 /proc/devices /proc/version
/proc/2681 /proc/7911 /proc/9797 /proc/diskstats /proc/version_signature
/proc/2926 /proc/8646 /proc/9800 /proc/dma /proc/vmcore
/proc/2929 /proc/8934 /proc/9803 /proc/driver /proc/vmstat
/proc/3 /proc/8935 /proc/9804 /proc/execdomains /proc/zoneinfo
/proc/3046 /proc/8945 /proc/9808 /proc/fb
/proc/3760 /proc/8970 /proc/9815 /proc/filesystems
ray@ray-desktop:~$

And as another note, even 'though I've used the -d switch to show only
directories in the output I'm still getting filenames with it. I also
expected the command to keep recursing into the subdirectories of /proc/
and list the directories there, but no such luck. What gives? Here's
what the man page says -

-d, --directory
list directory entries instead of contents, and do not dereference
symbolic links

-R, --recursive list subdirectories recursively

I still don't know how to get it to dig deeper and give me all of the
subdirectories, or how to get it to actually output only directory names.

And you wouldn't believe the amount of time it took me to formulate the
following command to get what I wanted.

find -maxdepth 1 -printf '%f %T+\n' | sort -s -t ' ' -k 2.1nr -k 2.6n -k
2.9n -k 2.12r -k 2.15 -k 2.18

From the find man page below you will note that it doesn't mention the
fact that the printf parameters need to be quoted to work.

-printf format
True; print format on the standard output, interpreting ‘\’
escapes and ‘%’ directives. Field widths and precisions can be
specified as with the ‘printf’ C function. Please note that
many of the fields are printed as %s rather than %d, and this
may mean that flags don’t work as you might expect. This also
means that the ‘-’ flag does work (it forces fields to be left-
aligned). Unlike -print, -printf does not add a newline at the
end of the string. The escapes and directives are:

And here is the skimpy info in the sort man page for the -k parameter. -

-k, --key=POS1[,POS2]
start a key at POS1, end it at POS2 (origin 1)

It neglects to mention that you can add further switches to each field
to affect their behavior, or that their use within the fields required
that you drop their leading '-' or they will not work. I had to further
read the info pages, and examine many example calls for things I wasn't
trying to do, to finally figure it out after many frustrating hours of
trying everything I could think of to get the commands to work.

I remember programming in DOS batch language, and I never had this much
trouble understanding the syntax because it was right there in the docs.

Again -

doc-writing-behavior --verbose --verbose

Later, Ray Parrish

--
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