vi: do not truncate file to zero length. closes bug 2944.

function                                             old     new   delta
file_write                                            98     104      +6

diff --git a/editors/vi.c b/editors/vi.c
index 454cfcee47ea4ceee0f3fda1fcb23053b15fba77..4e5a5ac4a278ffc1afdb18d8487a095e21f25448 100644 (file)
--- a/editors/vi.c
+++ b/editors/vi.c
@@ -2437,11 +2437,16 @@ static int file_write(char * fn, char * first, char * last)
                return -2;
        }
        charcnt = 0;
-       fd = open(fn, (O_WRONLY | O_CREAT | O_TRUNC), 0666);
+       /* By popular request we do not open file with O_TRUNC,
+        * but instead ftruncate() it _after_ successful write.
+        * Might reduce amount of data lost on power fail etc.
+        */
+       fd = open(fn, (O_WRONLY | O_CREAT), 0666);
        if (fd < 0)
                return -1;
        cnt = last - first + 1;
        charcnt = full_write(fd, first, cnt);
+       ftruncate(fd, charcnt);
        if (charcnt == cnt) {
                // good write
                //file_modified = FALSE; // the file has not been modified