cp: replace ambiguous text (#4223)

pages/common/cp.md

@@ -4,19 +4,19 @@
 
 - Copy a file to another location:
 
-`cp {{path/to/file.ext}} {{path/to/copy.ext}}`
+`cp {{path/to/source_file.ext}} {{path/to/target_file.ext}}`
 
 - Copy a file into another directory, keeping the filename:
 
-`cp {{path/to/file.ext}} {{path/to/target_parent_directory}}`
+`cp {{path/to/source_file.ext}} {{path/to/target_parent_directory}}`
 
 - Recursively copy a directory's contents to another location (if the destination exists, the directory is copied inside it):
 
-`cp -R {{path/to/directory}} {{path/to/copy}}`
+`cp -R {{path/to/source_directory}} {{path/to/target_directory}}`
 
 - Copy a directory recursively, in verbose mode (shows files as they are copied):
 
-`cp -vR {{path/to/directory}} {{path/to/copy}}`
+`cp -vR {{path/to/source_directory}} {{path/to/target_directory}}`
 
 - Copy text files to another location, in interactive mode (prompts user before overwriting):
 
@@ -24,4 +24,4 @@
 
 - Dereference symbolic links before copying:
 
-`cp -L {{link}} {{path/to/copy}}`
+`cp -L {{link}} {{path/to/target_directory}}`