-N means --no-buffer, but the original option name is --buffer.
So we need to negate it one more time (or one less time).

---
 I came across this while working on another issue that is
 highly dependent on output being unbuffered.
 On a side note, would a patch to change the nobuffer code
 path to use plain write(2) be accepted?  It would save some
 data copies to provide a small speedup.
 src/main.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/src/main.c b/src/main.c
index 9f3970d..d00ede8 100644
--- a/src/main.c
+++ b/src/main.c
@@ -2635,7 +2635,7 @@ static ParameterError getparameter(char *flag, /* f or -long-flag */
       break;
     case 'N':
       /* disable the output I/O buffering */
-      config->nobuffer = (bool)(!toggle);
+      config->nobuffer = (bool)(longopt ? !toggle : toggle);
       break;
     case 'O': /* --remote-name */
       if(subletter == 'a') { /* --remote-name-all */
-- 
Eric Wong
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