How to detect file ends in newline?
@Konrad: tail does not return an empty line. I made a file that has some text that doesn't end in newline and a file that does. Here is the output from tail:
$ cat test_no_newline.txtthis file doesn't end in newline$ $ cat test_with_newline.txtthis file ends in newline$Though I found that tail has get last byte option. So I modified your script to:
#!/bin/shc=`tail -c 1 $1`if [ "$c" != "" ]; then echo "no newline"fi
Or even simpler:
#!/bin/shtest "$(tail -c 1 "$1")" && echo "no newline at eof: '$1'"But if you want a more robust check:
test "$(tail -c 1 "$1" | wc -l)" -eq 0 && echo "no newline at eof: '$1'"
Here is a useful bash function:
function file_ends_with_newline() { [[ $(tail -c1 "$1" | wc -l) -gt 0 ]]}You can use it like:
if ! file_ends_with_newline myfile.txtthen echo "" >> myfile.txtfi# continue with other stuff that assumes myfile.txt ends with a newline