On Wed, Dec 02, 2015 at 04:20:59PM +0300, Alexander Zarochentsev wrote: > > BAD: if (rc != 0) > > GOOD: if (rc) > > The latest suggestion is not correct, > from http://wiki.lustre.org/Lustre_Coding_Guidelines : > Conditional boolean (if (expr)), scalar (if (val != 0)) and pointer > (if (ptr != NULL)) expressions should be written consistently. Kernel style trumps Lustre style. Double negative don't not hurt readability. != NULL is a checkpatch.pl warning. Also comparisons like == false or == true are checkpatch warnings. I can think of two places where comparing with zero is appropriate and those are: 1) If you are talking about the numer zero. if (x == 0 || x == 2) 2) strcmp() and other *cmp() functions. if (strcmp(foo, bar) == 0) /* foo and bar are the same */ if (strcmp(foo, bar) < 0) /* foo less than bar */ if (strcmp(foo, bar) != 0) /* foo not the same as bar */ For "if (rc) {" a zero return doesn't mean zero, it means success so comparing against zero is bad style. regards, dan carpenter _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
