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This page compiles questions on technical issues that I am (or was) frequently asking myself, along with the answers.
If you don't know the old directory name, do a svn checkout of the new directory first and examine the log with svn log -v. Next clone the old and new directories using git svn clone or svn2git, and add the old repository as a remote of the new repository. Then do a git log and note the oldest commit of the master branch, and do a git log old and note the newest commit of the old branch. Then join the two branches and clean up the repository. All together:
mkdir old-dir new-dir cd old-dir svn2git --notrunk --notags --nobranches --verbose old-svn-dir cd ../new-dir svn2git --notruck --notags --nobranches --verbose new-svn-dir git remote add old ../old-dir git fetch old OLDEST_COMMIT_OF_MASTER=$(git log --format=format:%H | tail -1) NEWEST_COMMIT_OF_OLD=$(git log --format=format:%H old/master | head -1) git replace "$OLDEST_COMMIT_OF_MASTER" "$NEWEST_COMMIT_OF_OLD" git filter-branch git remote rm old rm -rf .git/refs/replace
Source: How do I keep SVN history in Git when trunk has moved?
How do I keep SVN history in Git when trunk has moved?
git clean -x -d --dry-run # Check the output git clean -x -d --force
If you have the SSH_ASKPASS evironment variable set to ksshaskpass, then Git will use Ksshaskpass to prompt for credentials and then store these with KWallet. Future pushes and fetches will automatically use the credentials from KWallet. To remove or change these credentials, you need to do this from KWallet. On Plasma 5, you can do this by launching kwalletmanager5 --show. (Do not run kwalletmanager; this opens your KDE 4 wallet.) The Git credentials are stored in the ksshaskpass folder.
Use a lock file:
/usr/bin/flock -n /path/to/lockfile -c /path/to/program
(Omit the -n if you want to wait rather than fail if the lock cannot be acquired.)
du -h | sort -h
grep --color='auto' -P -n "[\x80-\xFF]"
Try one of the following:
cat /etc/*-release
lsb_release -a
First, make an SSH connection as follows:
ssh -D SOME_PORT SOME_HOST
Then configure your browser to use 127.0.0.1:SOME_PORT as a SOCKS v5 proxy.
Say you are connected to a remote host via SSH, and want to launch a VPN connection on that host where the connection replaces the default gateway. Normally this will cause the SSH connection to hang. To avoid this, first add a routing rule such that connections to the SSH client always use the original gateway:
sudo route add -host ${SSH_CLIENT%% *} gw $(/sbin/ip route | awk '/default/ { print $3 }')
Source: Prevent SSH connection lost after logging into VPN on server machine
Prevent SSH connection lost after logging into VPN on server machine
Enter ~ .
On openSUSE, install the geoip add-on for xtables:
sudo zypper in xtables-addons xtables-geoip
Now you can use iptables or the firewalld front end to it (if it is running) to block network traffic for a list of countries:
iptables -I INPUT -m geoip --src-cc CN,VN,ID,IN,KR,SG,HK -j DROP firewall-cmd --direct --add-rule ipv4 filter INPUT 0 -m geoip --src-cc CN,VN,ID,IN,KR,SG,HK -j DROP
If using firewalld, then to make the block persistent across reboots:
firewall-cmd --runtime-to-permanent
(eval-after-load "latex" '(add-to-list 'LaTeX-verbatim-macros-with-braces "index"))
(add-hook 'bibtex-mode-hook
(lambda () (setq fill-column 999999)))
If your document uses a custom LaTeX style or class, AUCTeX won't apply the correct style hooks. You need to create a custom Elisp style file specifying these hooks. You can try having AUCTeX automatically generate such a style file by running M-x TeX-auto-generate. You'll first be prompted for the path to the LaTeX style or class file, and then to the AUCTeX style directory (normally $HOME/.emacs.d/auctex/style) for output. The generated style file will have the same basename as the input file, but with a .el suffix. Open it and edit it as necessary.
A dual-monitor setup is convenient for having many windows open simultaneously. For example, it is common to have an Emacs window editing a LaTeX file on one monitor and a PDF viewer to view the output on the other monitor. But sometimes all you have are two separate machines, each with a single monitor (such as two laptops, or a laptop and a desktop). If you have the xpra tool installed on both machines, you can emulate a dual-monitor setup.
Let's assume that you want to run Emacs on the machine desktop and have the PDF viewer display on the machine laptop. First, start an xpra server on desktop using a display port of your choice:
[user@desktop]$ xpra start :700
Next, have laptop attach to desktop's xpra server:
[user@laptop]$ xpra attach ssh:user@desktop:700
Finally, in the Emacs running in desktop, start launching the PDF viewer using the usual C-c C-c View. When prompted for the command, insert DISPLAY=:700 at the beginning of the line. For example:
DISPLAY=:700 okular --unique foo.pdf
The nice thing about this is that it works with SyncTeX. That is, you can still type C-c C-v anywhere in your source document on desktop, and the PDF viewer on laptop will jump to the corresponding location in the PDF. Conversely, you can shift+click (or control+click, depending on the viewer) in the PDF viewer on laptop, and the Emacs running on desktop will jump to the corresponding source line.
When you are done editing, you can run xpra stop :700 on desktop to stop the xpra server. The client on laptop will automatically detach itself.
rpm -qf /path/to/file
zypper si -d packagename
Certain discourteous programs do not provide an uninstall target in their Makefiles. A solution is to install these programs to a dedicated prefix, and then use GNU Stow to add symlinks to the system directories:
./configure --prefix=/usr/local/stow/PROGRAM_NAME --libdir=/usr/local/stow/PROGRAM_NAME/lib64 make sudo make install cd /usr/local/stow sudo stow PROGRAM_NAME
qdbus org.kde.ksmserver /KSMServer logout 0 0 0
As of Plasma 5, it is no longer possible to fine-tune the system locale settings. For example, you cannot have KDE format currencies according to one locale, times and dates according to another locale, etc. Instead you can specify only a single, global locale.
For times and dates, you can globally override the default locale by setting LC_TIME (for example, in $HOME/.i18n on openSUSE). Alternatively, you can override on a per-application basis by manually setting LC_TIME before launching the application.
Unfortunately, you cannot specify a date/time format of your own choosing, but must select from among the locales installed on your system. Even more unfortunately, there is no easy way of knowing which of the locales (if any) format the date and time the way you want. Finding the right locale may be a matter of trial and error. Writing a new locale definition is supposed to be "easy" but is actually anything but (at least on openSUSE).
For ISO 8601–style dates, using the en_DK locale sometimes works. So for example, to have a certain application display dates in YYYY-MM-DD format, you can put the following script somewhere in your execution path:
#!/bin/bash LC_TIME=en_DK.UTF-8 exec /usr/bin/some_application "$@" >&/dev/null &
To have all applications display dates in this format, put the following in $HOME/.i18n or somewhere else that your shell will source it:
export LC_TIME="en_DK.UTF-8"
Unfortunately, the locale setting does not work with recent versions of Thunderbird due to reasons explained in Thunderbird Bug 1426907.
For further discussion, see KDE Bug 340982 and Thunderbird Bug 1509096.
In Plasma 5, popups such as the Application Launcher can be resized by holding down the Alt key and dragging with the right mouse button. Unfortunately, the new size is not persistent across logins. (See KDE Bug 332512.)
Persistently changing the size of the Application Launcher requires changing the values of Layout.minimumWidth and/or Layout.minimumHeight in its FullRepresentation.qml file, which by default lives in /usr/share/plasma/plasmoids/org.kde.plasma.kickoff/contents/ui. Changing this file will change the Application Launcher size for all users (which may or may not be what you want). However, the changes may get overwritten whenever Plasma is upgraded.
To change the size of the Application Launcher for a single user, copy /usr/share/plasma/plasmoids/org.kde.plasma.kickoff/ to $HOME/.local/share/plasma/plasmoids/org.kde.plasma.mykickoff/ and edit the contents/ui/FullRepresentation.qml file in the latter directory.
Source: Menu size. Resize or going to be Resizable?
Menu size. Resize or going to be Resizable?
Once upon a time, this was done by including the package times, though this failed to set Times as the math font. Later it was recommended to use mathptmx, which set Times for both the text body and math. But both packages are now obsolete. The following packages should be used instead:
\usepackage{newtxtext} % Use Times for main text
\usepackage{newtxmath} % Use Times for math
Note that this isn't quite the same as using times, since times also changes the default monospace font to Courier whereas newtxtext does not. If it's important to also change the monospace font to Courier, then the following code should also be added:
\DeclareRobustCommand\crfamily{\fontfamily{pcr}\selectfont}
\DeclareTextFontCommand{\texttt}{\crfamily}
\setcounter{biburlnumpenalty}{100} % Allow breaking at numbers (for DOIs)
\usepackage[dashed=true]{biblatex}
\renewcommand{\bibnamedash}{\rule[3pt]{3em}{0.7pt} } % long dash for repeated authors
\renewcommand*{\nameyeardelim}{\addcomma\space} % comma between author and year in citations
\renewrobustcmd*{\bibinitdelim}{\,} % thin space between author initials
\makeatletter
\@for\next:=collection,inbook,incollection,proceedings,book,inproceedings,thesis\do{%
\xpatchbibdriver{\next}
{{\printfield{isbn}}}
{{\printfield{issn}\newunit\newblock\printfield{isbn}}}
{}{}%
}
\makeatother
Instead of using the volume field, put the volume number in the number field. Then use the following:
% Formatting of numbered series
\DeclareFieldFormat[book,inbook,collection,incollection,proceedings,inproceedings]{number}{\bibstring{volume}~#1 \bibstring{ofseries}}
\renewbibmacro*{series+number}{%
\printfield{number}%
\setunit*{\addspace}%
\printfield{series}%
\newunit%
}
% For periodicals and articles, set volume and number as "volume(number)"
\xpatchbibmacro{volume+number+eid}{%
\setunit*{\adddot}%
}{%
}{}{}
\xpatchbibmacro{title+issuetitle}{%
\setunit*{\adddot}%
}{%
}{}{}
\DeclareFieldFormat[article,periodical]{number}{\mkbibparens{#1}}
% Suppress quotation marks around article and thesis titles
\DeclareFieldFormat
[article,inbook,incollection,inproceedings,patent,unpublished]
{title}{#1\isdot}
\DeclareFieldFormat
[thesis]
{title}{\emph{#1\isdot}}
% Full long citations (including all authors)
\makeatletter
\newcommand{\tempmaxup}[1]{\def\blx@maxcitenames{\blx@maxbibnames}#1}
\makeatother
\DeclareCiteCommand{\longfullcite}[\tempmaxup]
{\usebibmacro{prenote}}
{\usedriver
{\DeclareNameAlias{sortname}{default}}
{\thefield{entrytype}}}
{\multicitedelim}
{\usebibmacro{postnote}}
options = {dataonly=true},
PowerPoint 2010 has the ability to export to PDF, but this works only for entire slides. To export a single selection, use the following procedure:
1. Right-click on the graphic. Select Size and position… → Size. Note the height and width. Press Close.
2. Copy the graphic (Ctrl+C).
3. Create a new presentation (Ctrl+N).
4. Design → Page Setup. Change the height and width to the values you noted previously. (You may need to add a few millimetres to each dimension.) Press OK.
5. Right-click on the slide and select Paste Options: Picture.
6. File → Save & Send → Create PDF/XPS Document → Create PDF/XPS.
7. Set "Save as type" to "PDF (*.pdf)". Enter a filename and press the "Publish" button.
The various LibreOffice programs (Draw, Impress, etc.) claim to be able to export a selection to PDF, but a longstanding bug prevents this from working. Instead, they export the entire page, much like PowerPoint 2010. There are a number of possible workarounds:
Open the PDF file with a text editor and search for the /Catalog entry. Then append a /Pagelabels entry as follows:
/PageLabels << /Nums [ 0 << /P (cover) >> % labels 1st page with the string "cover" 1 << /S /r >> % numbers pages 2-6 in small roman numerals 6 << /S /D >> % numbers pages 7-x in decimal arabic numerals ] >>
Note that physical pages are numbered starting from 0.
Source: Renumber pages of a PDF
You can use pdfjam (also distributed with TeX Live). For example, to convert any PDF to A4:
pdfjam --outfile out.pdf --paper a4paper in.pdf
Last modified: 2021-08-08 21:36 CEST