search

apps7 c3 design16 git17 javascript1 jquery1 mac17 math‑ish3 matlab2 mercurial1 python13 rails13 random18 ruby38 tex7 todo4 tools22 use‑this‑cmd22 use‑this‑code8 vim16 writings2

Mar 8

spaces in filenames with rsync tools

Having spaces in filenames is, in general, reprehensible. However, if you’re dealing with something like an iPhoto Library, it’s not up to you. To deal with this in rsync, note the following, from this page.

# Copy three separate files on host to tmp.
rsync -av host:'file1 file2 file3' /tmp/

# Copy one file from host to tmp. ? matches any character.
rsync -av host:a?long?filename /tmp/
rsync -av host:'"a long filename"' /tmp/
rsync -av host:'a\ long\ filename' /tmp/
rsync -av host:a\\\ long\\\ filename /tmp/

Feb 24

ired lite—control preview via the apple remote mac, tex, tools

Finally, a decent way of controlling preview on the mac via the apple remote. iRed Lite works well, and finally makes it possible to use the remote for texed presentations.

Feb 16

track maximum memory usage of a process tools

Apparently, “the memmon executable monitors a linux process and provides summary statistics about the memory usage of the process after it terminates.”

Jan 12

geokit gem ruby, tools

The geokit gem for ruby is extremely good. Within seconds of installing it I could use it to look up locations and distances. Now to apply this to analyzing tracks made by runkeeper, exported to gpx format, processed with hpricot, and bound together with much ruby goodness.

Oct 29

rake ruby, tools

Some more details about using rake.

And this page talks about some options when you want the output folder to be different to the input.

Oct 20

more bash features / pwd tools

Bash seems to contain more features than I could ever imagine. Check this out, for example:

# Both lines will produce the same output, but the first is a variable.
echo ~+
pwd

Oct 15

rake ruby, tools

Surely rakefiles are the future. GNU Make just looks antiquated.

Update: not so sure. Rake seems like it’s not that great after all. I might try writing my own sometime.

Oct 15

rake tab completion ruby, tools

Rake tab completion for bash.

Sep 23

curl mac, tools, use-this-cmd

Download a file, much like wget, but with curl:

curl -O http://example.com/file.sty
# equivalent to
wget http://example.com/file.sty

This is especially appropriate on mac, because curl comes with mac, unlike wget.

Sep 15

convert pdf to png tools, use-this-cmd

Converting a pdf to a png and making it 1000x1000 pixels:

convert -density 300x300 -resize 1000x1000 infile.pdf outfile.png

Jun 19

hush login tools, use-this-cmd

Sick of messages like this when logging in?

Last login: Thu May 21 23:31:00 2009

Simply

touch .hushlogin

and they’ll be all gone.

Jan 31

xdvi tools

The letter k toggles keep mode in xdvi; with keep on, the horizontal and vertical page offset remains the same, even when switching pages.

Jan 30

batch rename files in bash todo, tools, use-this-cmd

Let’s say we want to remove the prefix one from a series of files. Use this:

for FILE in one* ; do mv $FILE `echo $FILE | sed 's/one//'` ; done

Or, use +rename+. Thanks to the reader who pointed out that, in Debian GNU Linux (for example), you can also use rename, as in

rename 's/^one//' one*

Much cleaner, if rename is available.

Sep 2

expire a user’s password tools, use-this-cmd

Expire a user’s password, requiring them to change it immediately upon their next login:

passwd -e username

Aug 21

valgrind tools, use-this-cmd

Check for common memory errors in C with valgrind. Also profile cache misses and branch mispredictions.

Sample usage:

# Check memory accesses.
valgrind --tool=memcheck ./prog

# View cache and branch profiling information.
valgrind --tool=cachegrind ./prog

For more detailed output from valgrind, add the -g tag to your gcc compilation flags to add debugging information to the binary.

Aug 13

multi-process make tools

Use multiple processes (and hence cores) with make by using make -j.

Aug 13

disconnect ssh quickly tools

Disconnect ssh quickly, even when ^d is not allowed, with ~..

Aug 11

tee tools, use-this-cmd

A reminder of how tee works comes from hunterdavis.com.

./prog | tee >(gzip > logfile.tgz)

Aug 11

find and sed on mac mac, tools, use-this-cmd

find and sed operate slightly differently on a mac. Here’s some code that replaces 4.3 with 4.4 in all Makefiles, recursively.

find . -name 'Makefile' -exec sed -i -e 's/4\.3/4.4/g' {} \;

Aug 4

gcc assembly output etc. c, tools

To see the assembly instructions generated for a piece of C code, use this:

gcc -c -g -Wa,-ahl src.c

Find out the macros, and values, predefined by gcc (includes useful things like __INT_MAX__).

gcc -dM -E - < /dev/null

Jul 29

find tools, use-this-cmd

I’ve often tried to use find, but have never really got over its syntax. It seems that it’s one of those powerful tools that’s not necessarily obvious to use at first.

Here’s one way to use it. This:

find . -name '*.sw*' -print

prints filename which have .sw in them (say, leftover vim swapfiles).

You can combine this with grepping. This:

find . -name "*.bib" -exec echo {}; grep "tribute to" '{}'

looks for the words ‘tribute to’ in files with the extension .bib.

Jul 22

display optimization flags available in gcc c, tools

Version 4.3 of gcc, has some significant improvements (more info), including this nice feature:

>> gcc -c -Q -Os --help=optimizers
The following options control optimizations:
  -falign-jumps                         [disabled]
  -falign-labels                        [disabled]
  -falign-loops                         [enabled]
# ...
  -fwhole-program                       [disabled]
  -fwrapv                               [disabled]

jemnotesversion 2 / featuring tools or see all/search

jem notesversion 2 / featuring tools or see all/search