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--- bash:files:read_a_file:troubleshooting:files_lack_their_final_newlines [2021/01/26 14:14] – created peter
+++ bash:files:read_a_file:troubleshooting:files_lack_their_final_newlines [2021/01/26 14:17] (current) – peter
@@ Line 1: / Line 1: @@
 ====== BASH - Files - Read a file - Troubleshooting - Files lack their final newlines ======
+===== My text files are broken!  They lack their final newlines! =====
+If there are some characters after the last line in the file (or to put it differently, if the last line is not terminated by a newline character), then **read** will read it but return false, leaving the broken partial line in the read variable(s).
+You can process this after the loop:
+<code bash>
+# Emulate cat.
+while IFS= read -r line; do
+  printf '%s\n' "$line"
+done < "$file"
+[[ -n $line ]] && printf %s "$line"
+</code>
+or:
+<code bash>
+# This does not work:
+printf 'line 1\ntruncated line 2' | while read -r line; do echo $line; done
+# This does not work either:
+printf 'line 1\ntruncated line 2' | while read -r line; do echo "$line"; done; [[ $line ]] && echo -n "$line"
+# This works:
+printf 'line 1\ntruncated line 2' | { while read -r line; do echo "$line"; done; [[ $line ]] && echo "$line"; }
+</code>
+<WRAP info>
+**NOTE:**
+The first example, beyond missing the after-loop test, is also missing quotes.
+</WRAP>
+----
+Alternatively, you can simply add a logical OR to the while test:
+<code bash>
+while IFS= read -r line || [[ -n $line ]]; do
+  printf '%s\n' "$line"
+done < "$file"
+printf 'line 1\ntruncated line 2' | while read -r line || [[ -n $line ]]; do echo "$line"; done
+</code>
+----