Rename a dir

command-line-utils/gotchas.md

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+If you are working in command line and want to assign some keybinding to something, be careful if you want to use `<C-m>` (a.k.a `<Ctrl-m>`). This is **same** as sending `<Enter>` to the terminal which might not be what you want. 

command-line-utils/joining-images-into-one.md

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+You can join multiple images into one using `convert`:
+  
+    # join vertically
+    convert in1.png in2.png -append out.png
+
+    # join horizontally 
+    convert in1.png in2.png +append out.png

command-line-utils/joining-images-to-pdf.md

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+You can join multiple images to pdf using `convert`:
+
+    convert *.png out.pdf
+
+If you get an error like 
+
+    convert-im6.q16: attempt to perform an operation not allowed by the security policy `PDF' @ error/constitute.c/IsCoderAuthorized/408.
+
+follow the steps below:
+
+    sudo vim /etc/ImageMagick-6/policy.xml
+
+and replace the line 
+
+    <policy domain="coder" rights="none" pattern="PDF" />
+
+with
+
+    <policy domain="coder" rights="read|write" pattern="PDF" />
+
+
+[source](https://askubuntu.com/questions/1081895/trouble-with-batch-conversion-of-png-to-pdf-using-convert)

command-line-utils/joining-pdf-files.md

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+You can join multiple pdf files into one using this command:
+
+```
+pdfunite in-1.pdf in-2.pdf in-n.pdf out.pdf
+```
+
+Make sure to provide output file name otherwise last input file will be overwritten.

command-line-utils/splitting-pdf-files.md

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+You can extract certain parts of a pdf file with this:
+
+```
+pdfjam original.pdf 5-10 -o out.pdf
+```
+
+If `pdfjam` is not installed, you can try doing it with GUI. Search for "Print to file" option.

command-line-utils/virtual-environment-with-system-packages.md

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+You can use below command to create a virtual environment which contains installed packages:
+```
+virtualenv venv --system-site-packages
+```