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Shyy erny anzr - Naqernf Rvonpu


1d
comment Trying to access environment variable (array) declared in ~/.profile from shell script
I don’t understand why you view this as a hardship. Because the script might be called repeatedly in short intervals. And hence I thought it would be a nice idea to have an array pre-built which can then be used by all subsequent script calls.
Sep
10
comment awk: Extracting a fixed number of rows where the last row number may vary
Speaking of which, some regex engines even do use angle brackets for word boundary matching :) (however they won't work in either awk or gawk) ... Anyways, I think it'll be worth working on a solution that will simulate word boundary on non-GNU awk, since the blind following of GNUisms has almost become epidemic on SE/SO, and thus one of my pet peeves as well.
Sep
10
comment awk: Extracting a fixed number of rows where the last row number may vary
Caveat: Make sure you keep in mind that a \b in GNU awk (gawk) will stand for backspace, so to work correctly, the regex in my OP must be changed to / \ytop\y$/, with \y` standing for "word boundar y". This has just cost me another 15 minutes to figure out, since my regex made top keep on spitting out itself all the same, although I was sure I had filtered it out by now....BUT: this is a GNU-ism; it's not available in traditional awk implementations (neither is \b).
Sep
10
comment awk: Extracting a fixed number of rows where the last row number may vary
@G-Man Well, top displays the stuff pre-sorted already, whilst with ps you'd normally have to pipe a sort to the line to achieve the same. Unless you know about the --sort option in ps, which I had ignored...
Sep
9
comment awk: Extracting a fixed number of rows where the last row number may vary
Thank you! That might already be the solution. And I have nothing against your italics, for it leaves those who ask a little chance to think themselves. :) I'd always just need these general ideas, not everything word-by-word. BTW, about the count=5 bit: very sneaky! I was trying so hard with for loops, but got nowhere (except for silly output as well as annoying and totally confusing error messages from awk)
Sep
9
comment awk: Extracting a fixed number of rows where the last row number may vary
Very nice alternate solution as well, thanks! Might even take less resources than the top approach.
Sep
1
comment wget: Retrieving a list of URLs when modifying input data file on the fly
Well, the basic problem is that there were two very useful comments which ought to have been posted as answers. However I guess this has been done on purpose, because both of the commenters were not entirely sure since they could not "live-test" it at the moment they posted it. So both of them or just one may turn theirs into an answer, and I'll put the checkmark on it. But not on my own one, that's silly.
Sep
1
comment wget: Retrieving a list of URLs when modifying input data file on the fly
@garethTheRed You're a marvel. Doing them in this order works. Thank you very much. But thanks as well to Mark for the alternate solution, which works if you use wget -nc -i <(cut -f1 -d' ' inp). No dollars here. :)
Aug
30
comment Use find to find certain directory and delete all files in it except one directory
Yes I agree it IS better than the great part of the other Bash PF articles. (I never link you to any pointless crap, mind you :)) And thanks for the link.
Aug
30
comment Use find to find certain directory and delete all files in it except one directory
Well, you're the first to complain about me linking it. Seriously. Though not all "tips" might be the creme de la creme, there are lots of neat tricks in there that have helped me many times. Still, I'm no "gregwoo fanboi" - but I wouldn't go as far as daring accuse him of "ignorance" either.
Aug
30
comment Use find to find certain directory and delete all files in it except one directory
Well it was supposed to mean that the first subshell doesn't know anything of the second, if there are two. And so things might give different results as you would expect because both subshells are independent of each other. But you might expect parameters to be "known" to both. (Heck, you even used export, so why doesn't that work?) However, you debug variables and get zero length and other nonsense. YMMV...but since I've avoided cd in scripts and specified paths directly instead, my scripts are less prone to errors. mywiki.wooledge.org/BashPitfalls#cd_.2Ffoo.3B_bar
Aug
30
comment find: Why is the -a operator not commutative in combination with -print?
Looks excellent now in my opinion. Thanks for your agreement on improvement. As you have seen, this stuff is way trickier than it looks at first.-- Lastly, this has now turned a great solution for alias as well. Remember, alias needs the argument at the EOL, and the -print was in the way all the time. Thanks to your marvellous "dummy option" -a -name ., this is now feasible. Fantastic! Thank you.
Aug
30
comment find: Why is the -a operator not commutative in combination with -print?
Well, that's not quite the same. Try it out. "./exclude_me" does get listed once you omit the -print at the end of the line. But I want it both excluded and not even listed at all. Not until you add the explicit -print, however, "exclude_me" will actually be left out of the listing. Trust me, I can try here "live" and I know what I'm talking about :)
Aug
30
comment Use find to find certain directory and delete all files in it except one directory
Well, I think the downvote is fully justified in this case. It always makes my toenails roll up whenever I see cd in a shell script. This will cause nothing but trouble. Think of shell sessions, subshells, subshell A not knowing anything of subshell B and their parameters and vice versa---and so on. Avoid.
Aug
29
comment Why do we use double hyphen in “tar --anchored” and single hyphen in “tar -b”?
@Zeke Ugh! Don't you remind me of that.
Aug
29
comment Why do we use double hyphen in “tar --anchored” and single hyphen in “tar -b”?
I guess it's pretty simple. tar (= "tape archiver", think of QIC-80 and friends) is a VERY old command from the beginnings of UNIX, and in the old days, there were only those said -X options. I've scoured the man page, and I can't remember any tar option being available from the old days that took 2 dashes. Hence, there is a rule of thumb that all of the latter ones are commands which were added much later during recent years.
Aug
25
comment How to set conkys window width?
Yes, but it will only work every second time when .conkyrc is edited with gedit, as I've found out. So you edit it, save the file - nothing happens. You edit it again (a pseudo-edit might do)...and all of a sudden, conky will detect the config file change and restart automatically.
Aug
25
comment conky: proper column alignment
conky -D might come in handy as well perhaps (will put conky into debug mode, letting you peek way more deeply into its inner workings, and maybe giving you a clue what your build of conky is "allergic" against)
Aug
24
comment diskio/diskiograph in Conky only understands physical device names?
And again you're right!! Once I omit the parameters, I get ugly colors and wrong height, but yes it works! However, I can't accept this. I ought to file a bug report that the parameters will actually "kill" the graph when no physical device name is given.
Aug
24
comment diskio/diskiograph in Conky only understands physical device names?
Well, my whole line is ${diskiograph /dev/disk/by-uuid/1234567890ABCDEF 15, 130 828282 7f8ed3 0.1 -l}. Since there are a decent lot of parameters following the UUID, it's only natural that there is a space after it. :) diskio is not diskiograph; the former does not take any parameters.