Stupid Computing Notes

I am not good at using computer just like you, so I need to take notes for some stupid tips and howtos.

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Yosemite logical volumes cannot be read on Windows bootcamp anymore since they are not HFS+ volumes but they are now CoreStorage.

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Remove unnecessary Windows 10 entries from rEFInd

rEFInd detects unnecessary entries for Windows 10. This is how I removed them.

rEFInd is now installed under the ESP volume if you choose default installation on OS X 10.10 Yosemite or later. So, mount it first, then edit the conf file next.

mkdir /Volumes/esp sudo mount -t msdos /dev/disk0s1 /Volumes/esp vim /Volumes/esp/EFI/refind/refind.conf

refind.conf should have the commented line like #dont_scan_volumes "Recovery HD", so add an line the below:

#dont_scan_volumes "Recovery HD" dont_scan_volumes "BOOTCAMP","NTFS volume"

Then restart the Mac, you won't see the entries anymore.

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(Re)start specific background command

Useful when (re)start specific background command:

PID=$(ps aux | grep '<command>' | awk '{ print $2 }') [ -z "${PID}" ] && kill ${PID} nohup <command> 2>&1 | logger & unset PID

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One time job with at despite cron repeats

at is a command to execute one time job despite cron repeats the job.

at 3:30 AM << __JOBS__ whoami > ./whoami.txt __JOBS__

The example above will create whoami.txt in the current directory and put the result of whoami command at 15:30.

atq to check left jobs

atrm to delete a left job

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Generate pronounceable password

Generate it with pwgen:

pwgen -01A

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Remove conflicted copies of Dropbox

find | grep | xargs rm doesn't cope with file names having spaces, so I choose -name instead.

find . -type f -name '*conflicted copy *' -print0 | xargs -0 rm

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iTerm2 is a replacement for Terminal and the successor to iTerm

TotalTerminal dies sadly. iTerm2 has Quake-style visor just like TotalTerminal. This will be my alternative choice.

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Webhook service for cross-brower JavaScript testing CI. This seems dead though.

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List of icense identifiers

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Check log from Android Browser

Connect adb and;

adb logcat browser:V *:S

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Sort single line with space delimiter

xargs seems awesome:

echo 'B A C' | xargs -n 1 | sort | xargs

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Crop multiple image files at once with GraphicsMagick

Crop multiple images:

gm mogrify -output-directory ./OUTPUT_PATH -crop WxH+X+Y *.EXT

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Clear DNS cache on Mac OS X

Run the command below:

sudo killall -HUP mDNSResponder

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Note about CFLAGS & LDFLAGS

This may be helpful when you get errors during compiling source codes.

CFLAGS as environment variable sets PATH to include directory

LDFLAGS as environment variable sets PATH to lib directory

For example, adding another openssl from Homebrew to compile something:

CFLAGS="-I$(brew --prefix openssl)/include" LDFLAGS="-L$(brew --prefix openssl)/lib" make

This make you use specified openssl to make

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Git: Ignoring specific file from staging

Sometimes I want change some files that I don't want to stage the changes. For example, developing a web app on `localhost` and changing the configuration file temporary should be happens. Now Git supports this use case. If you want to ignore specific file from staging: git update-index --assume-unchanged And when you want to track changes again: git update-index --no-assume-unchanged This is useful when you want to stage everything by `git add -A` or something :D

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Concatenate multiple PDFs into a single PDF

Ghostscript will help you:

gs -q -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -sOutputFile=merged.pdf source1.pdf source2.pdf source3.pdf etc.pdf