cat: update placeholders (#8579)

pages/common/cat.md

@@ -5,20 +5,20 @@
 
 - Print the contents of a file to the standard output:
 
-`cat {{file}}`
+`cat {{path/to/file}}`
 
-- Concatenate several files into the target file:
+- Concatenate several files into an output file:
 
-`cat {{file1}} {{file2}} > {{target_file}}`
+`cat {{path/to/file1}} {{path/to/file2}} > {{path/to/output_file}}`
 
-- Append several files into the target file:
+- Append several files into an output file:
 
-`cat {{file1}} {{file2}} >> {{target_file}}`
+`cat {{path/to/file1}} {{path/to/file2}} >> {{path/to/output_file}}`
 
 - Number all output lines:
 
-`cat -n {{file}}`
+`cat -n {{path/to/file}}`
 
 - Display non-printable and whitespace characters (with `M-` prefix if non-ASCII):
 
-`cat -v -t -e {{file}}`
+`cat -v -t -e {{path/to/file}}`