scan-build complaint on cookie_interface.c

[bagder]

Unfortunately, #7490 caused scan-build to yell:

cookie_interface.c: In function ‘main’:
cookie_interface.c:96:53: error: ‘%.0lf’ directive output may be truncated writing between 1 and 310 bytes into a region of size 230 [-Werror=format-truncation=]
     snprintf(nline, sizeof(nline), "%s\t%s\t%s\t%s\t%.0lf\t%s\t%s",
                                                     ^~~~~
cookie_interface.c:96:5: note: ‘snprintf’ output between 70 and 379 bytes into a destination of size 256
     snprintf(nline, sizeof(nline), "%s\t%s\t%s\t%s\t%.0lf\t%s\t%s",
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
              ".example.com", "TRUE", "/", "FALSE",
              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
              difftime(time(NULL) + 31337, (time_t)0),
              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
              "PREF", "hello example, i like you very much!");
              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors

_Originally posted by @bagder in https://github.com/curl/curl/pull/7490#issuecomment-886606852_

[danielgustafsson]

Isn't %lf a C99 construct with undefined behavior in C89?

[bagder]

I suppose the l (ell) should be removed from there, right?

[danielgustafsson]

I suppose the l (ell) should be removed from there, right?

I think so, to make it C89 compatible. (I assume we stick to C89 for examples too?)

[bagder]

I think we should, if nothing else to make it easier for us to run the checkers and tools with the same conditions.