Gentoo Archives: gentoo-user

From: Dale <rdalek1967@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Dolphin and adding a option, if it exists.
Date: Tue, 22 Nov 2022 09:59:37
In Reply to: Re: [gentoo-user] Dolphin and adding a option, if it exists. by Frank Steinmetzger
1 Frank Steinmetzger wrote:
2 > Am Sun, Oct 23, 2022 at 01:35:55AM -0500 schrieb Dale:
3 >
4 >> Well, I ran into a slight problem.  This isn't much of a problem with
5 >> Linux but I'm not sure how this would work on windoze tho.  The problem,
6 >> if it is one, is the file extension.  Let's say I have a mp4 file that
7 >> is the older original file that I intend to replace.  If the file I
8 >> intend to put in its place is a .mkv file, mv uses the .mp4 extension
9 >> because all it cares about is the name of the file, not what it is or
10 >> its content.  So, I end up with a .mkv file that has a .mp4 extension. 
11 >> It works here on Linux but not sure about windoze and such.
12 > It’s not a problem for as long as the application you open the file with
13 > does its own detection. I.e. you feed mp4 to mpv, but it recognises by
14 > itself that it’s mp4 and can handle it.
15 >
16 >> I looked at the man page and I don't see a way to tell it to retain the
17 >> extension.  I see something about suffix but I don't think that is
18 >> related to this.  If I just backspace and change the extension, it
19 >> basically moves the file and I end up with both the old and new file.  I
20 >> wish I could write code and create a tool for this.  :/ 
21 >>
22 >> Is there a way to work around this problem?  It works great except for
23 >> losing the file extension. 
24 > If you still want to stick to a terminal solution akin to mv, then there is
25 > no way around a little script which wraps mv by extracting the extension and
26 > filename base. You could also add some “intelligence” with regards to
27 > directories, in order to reduce the amount of effort required to use the
28 > command—in case your directories follow some schema or are constant.
29 >
30 >
31 > #!/usr/bin/sh
32 >
33 > [ "$#" -ne "2" ] && exit 1
34 > SRC="$1"
35 > DST="$2"
36 >
37 > SRC_EXT="${SRC##*.}"
38 > DST_BASE="${DST%.*}"
39 >
40 > # remove destination for the case that the extensions differ
41 > rm "$DST"
42 >
43 > mv "$SRC" "${DST_BASE}${SRC_EXT}"
44 >
46 I finally got a chance to try this.  I saved it and made it executable. 
47 It runs but gave me this error. 
50 dmv torrent/video_name-old-place.mp4 video-name-new-place.mp4
51 bash: /bin/dmv: /usr/bin/sh: bad interpreter: No such file or directory
52 dale@fireball ~/Desktop/Crypt/Series $
55 My scripting skills are minimal at best.  Still, I kinda got what your
56 script was doing.  Those who have known me for a while understand how
57 miraculous that is.  ROFL  I did some googling.  It seems to not be able
58 to find the 'shebang' part.  Sure enough, sh isn't located in /usr/bin
59 here.  It's in /bin tho.  I edited that line so it can find it.  When I
60 tried it, it worked but noticed another problem.  It was leaving out the
61 dot, ".", before the extension.  Back into the script I went.  I revved
62 up my gears for a bit and made a edit.  When I tried it again, I was
63 shocked.  I almost fell in the floor.  Dang thing worked perfectly with
64 me only having to edit once.  I really did get how the script works,
65 sort of.  O_O 
67 This is the script as shown by cat:
70 root@fireball / # cat /bin/dmv
71 #!/bin/sh
73 [ "$#" -ne "2" ] && exit 1
74 SRC="$1"
75 DST="$2"
77 SRC_EXT="${SRC##*.}"
78 DST_BASE="${DST%.*}"
80 # remove destination for the case that the extensions differ
81 rm "$DST"
83 mv "$SRC" "${DST_BASE}.${SRC_EXT}"
84 root@fireball / #
87 I added a little . on that last line before the extension bit.  I'm a
88 happy camper.  Only thing is, turns out both source and destination file
89 have the same extension in this case.  Still, I bet it will work.  Then
90 I thought of a way to test this.  I just changed the extension on the
91 destination file and did a move.  I changed the .mp4 to .mkv on the
92 destination.  When I used your move script, it used the .mp4 extension
93 from the original source file but used the old name.  Perfect!!
95 Hope this makes the point.  THANK YOU MUCH!!!!
97 Dale
99 :-)  :-)


Subject Author
Re: [gentoo-user] Dolphin and adding a option, if it exists. Frank Steinmetzger <Warp_7@×××.de>