Batch FOR-Loops EOL relies on a rare character

[jeb-de]

In many batch files is a for-loop used like this

FOR /F "EOL=<rare-character> tokens=* delims="

It's used to fetch a full line and avoid skipping of lines, when they begin with the EOL character.

But using a rare-character has some drawbacks

• Code can not be copied to many forums (Like stackoverflow, Dostips, ...) because these characters are stripped
• Some editors can not handle theses characters well
• A real line/string can still start with such a character

All points can be solved by using an empty EOL character. To create such a FOR-loop, quoting must not be used

FOR /F tokens^=*^ delims^=#^ EOL^= %%L in (somefile) do echo ...%%L

Or when a string used, it can be even more simplified by enclosing the string in quotes and remove them later by using the %%~ syntax.

FOR /F "delims=" %%L in (""!string!"") do echo ...%%~L

Btw. "tokens=* delims=" can be simplified to "delims="

[andry81]

FOR /F "delims=" %%L in (""!string!"") do echo ...%%~L

What the difference with this:

FOR /F "delims=" %%L in ("!string!") do echo ...%%L

[jeb-de]

This sample shows the difference:

@echo off
setlocal EnableDelayedExpansion
SET "string=;Hello"
FOR /F "delims=" %%L in ("!string!") do echo FAIL: %%L
FOR /F "delims=" %%L in (""!string!"") do echo WORK: %%~L

Only the second FOR works, because the string always begins with a quote. Therefore there can never a problem with the EOL character. And the loop even works for empty strings, because they are enclosed in quotes

[andry81]

FOR /F tokens^=*^ delims^=#^ EOL^= %%L in (somefile) do echo ...%%L

I think you can shorten that to this:

FOR /F "tokens=* delims=#"^ EOL^= %%L in (somefile) do echo ...%%L

[jeb-de]

I think you can shorten that to this: FOR /F "tokens=* delims=#"^ EOL^= %%L in (somefile) do echo ...%%L

Yes, that works too and is even a bit simpler

[andry81]

Only the second FOR works, because the string always begins with a quote.

Yes, by default the ; is a quote character, so you can redefine it to empty:

FOR /F "delims="^ EOL^= %%L in ("!string!") do echo FAIL: %%L

And the loop even works for empty strings, because they are enclosed in quotes

Interesting, but must be tested on all Windows versions. Not sure it is stable.

[jeb-de]

Interesting, but must be tested on all Windows versions. Not sure it is stable.

I am quite sure that this already worked in XP. This is only another way to solve the EOL problem, for me it looks a bit better than the empty EOL variant and in some situations it is convenient that it can handle empty strings.

[andry81]

for me it looks a bit better than the empty EOL variant

It has an issue :smile:

@echo off
setlocal
set string=!
setlocal ENABLEDELAYEDEXPANSION
FOR /F "delims=" %%L in (""!string!"") do echo WORK: %%~L?

[jeb-de]

Not really 😄 The exclamation mark only disappears just after the expansion in "WORK: %%~L", because delayed expansion was active. For-Meta-variables always have this problem, because of the order of expansions.

@echo off
setlocal DisableDelayedExpansion
set string=!
setlocal ENABLEDELAYEDEXPANSION
FOR /F "delims=" %%L in (""!string!"") do (
    endlocal
    echo WORK: %%~L?
)

[andry81]

How about the case with a file read? You still have to use the empty EOL.

[andry81]

I've tested the ""!string!"" on XP/7/8, x86/x64. Seems works the same way for all 256 characters.