[nb] Edit: cli_commands.md

cli_commands.md

@@ -1,52 +1,81 @@
-# cli commands
-#cli
+# CLI Cheatsheet
 
-## display list of content types and # of associated nodes:
-drush sqlq 'select count(node.nid) as node_count, node_type.type from node inner join node_type on node.type = node_type.type group by node_type.type'
+## Contents
+- [Drupal / Drush](#drupal--drush)
+- [Text Processing](#text-processing)
+- [Torrents](#torrents)
+- [PDF Tools](#pdf-tools)
 
-## And then if you want filter by a specific type, just use grep like this:
-drush sqlq 'select count(node.nid) as node_count, node_type.type from node inner join node_type on node.type = node_type.type group by node_type.type' | grep 2014
+---
 
-## search replace in text mulitle files
+## Drupal / Drush
+
+> Note: These SQL queries target the Drupal 7 schema (`node_type` table). They won't work as-is on Drupal 8+.
+
+### List content types with node counts
+
+    drush sqlq 'select count(node.nid) as node_count, node_type.type
+                from node
+                inner join node_type on node.type = node_type.type
+                group by node_type.type'
+
+### Filter results by keyword (e.g. "2014")
+
+    drush sqlq 'select count(node.nid) as node_count, node_type.type
+                from node
+                inner join node_type on node.type = node_type.type
+                group by node_type.type' | grep 2014
+
+---
+
+## Text Processing
+
+### Find and replace inside files (perl)
+
+    # Single file type in current directory
     perl -pi -w -e 's/SEARCH_FOR/REPLACE_WITH/g;' *.txt
+
+    # Recursively across all file types
     perl -pi -w -e 's/thex/robertsonlibrary/g;' **/*.*
 
-## search replace in file names
+### Find and replace in file names
+
+    # Rename files matching a pattern, verbose output shows what changed
     rename 's/livero/lives/g' **/*.* -v
 
-## torrent download
+---
+
+## Torrents
+
+### Download via magnet link (aria2c)
+
+    # aria2c is a lightweight multi-protocol download utility
     aria2c -d ~/Downloads "magnetlink"
 
+---
 
-ocrmypdf --optimize 3 --skip-text input.pdf output.pdf
+## PDF Tools
 
+### OCR a PDF (ocrmypdf)
+
+    # Standard: optimize output, skip pages that already have a text layer
+    ocrmypdf --optimize 3 --skip-text input.pdf output.pdf
 
+    # Aggressive: force re-OCR even if a text layer exists (useful for corrupt/bad layers),
+    # set DPI manually, use page segmentation mode 1 (automatic with OSD)
     ocrmypdf --optimize 3 --image-dpi 300 --output-type pdf \
              --force-ocr --tesseract-pagesegmode 1 input.pdf output.pdf
 
-# down sample pdfs to 72dpi
-(single file)
+### Downsample a PDF to 72dpi (Ghostscript)
+
+    # Single file
     gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 \
        -dPDFSETTINGS=/screen \
        -dNOPAUSE -dQUIET -dBATCH \
        -sOutputFile=output.pdf input.pdf
 
-(batch)
-
-# In the folder with your PDFs
-mkdir downsampled
-
-for f in *.pdf *.PDF; do
-    [ -f "$f" ] || continue
-    gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen \
-       -dNOPAUSE -dBATCH \
-       -sOutputFile="downsampled/${f%.pdf}_72dpi.pdf" \
-       "$f"
-done
-# In the folder that contains your original PDFs
-
+    # Batch - processes all PDFs in current folder, preserves original filenames
     mkdir -p downsampled
-
     for f in *.pdf *.PDF; do
         [ -f "$f" ] || continue
         gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen \
@@ -55,21 +84,26 @@ for f in *.pdf *.PDF; do
            "$f"
     done
 
-# check current dpi
+### Check image DPI in PDFs (pdfimages)
+
+    # Print image info to terminal
     for f in *.pdf *.PDF; do
-    echo "=== Images in: $f ==="
+        echo "=== $f ==="
         pdfimages -list "$f"
         echo ""
     done
-# Creates (or overwrites) images_list.txt in the current directory
+
+    # Save output to images_list.txt instead
     for f in *.pdf *.PDF; do
-    if [ -f "$f" ]; then
-        echo "=== Images in: $f ===" >> images_list.txt
+        [ -f "$f" ] || continue
+        echo "=== $f ===" >> images_list.txt
         pdfimages -list "$f" >> images_list.txt
         echo "" >> images_list.txt
-    fi
     done
-# scan for ccitt encoding
+
+### Scan for CCITT encoding
+
+    # CCITT is a fax-era compression format - flags PDFs that may cause compatibility issues
     for f in *.pdf *.PDF; do
         [ -f "$f" ] || continue
         if pdfimages -list "$f" 2>/dev/null | grep -q " ccitt "; then