| OS | Man Page | Section | Hits |
|---|---|---|---|
| freebsd | catopen | 3 | 825 |
| mojave | catopen | 3 | 624 |
| redhat | catopen | 3 | 621 |
| hpux | catopen | 3c | 583 |
| opendarwin | catopen | 3 | 557 |
| suse | catopen | 3 | 545 |
| opensolaris | catopen | 3c | 532 |
| linux | catopen | 3 | 520 |
| osx | catopen | 3 | 507 |
| centos | catopen | 3 | 497 |
| xfree86 | catopen | 3 | 491 |
| v7 | catopen | 3 | 477 |
| sunos | catopen | 3c | 466 |
| debian | catopen | 3 | 457 |
| netbsd | catopen | 3 | 444 |
| ultrix | catopen | 3int | 422 |
| posix | catopen | 3p | 373 |
| osf1 | catopen | 3 | 356 |
| suse | catopen | 3p | 299 |
| centos | catopen | 3p | 293 |