| OS | Man Page | Section | Hits |
|---|---|---|---|
| freebsd | catopen | 3 | 369 |
| redhat | catopen | 3 | 266 |
| mojave | catopen | 3 | 262 |
| opendarwin | catopen | 3 | 254 |
| hpux | catopen | 3c | 242 |
| centos | catopen | 3 | 226 |
| v7 | catopen | 3 | 224 |
| linux | catopen | 3 | 221 |
| suse | catopen | 3 | 220 |
| ultrix | catopen | 3int | 218 |
| debian | catopen | 3 | 216 |
| sunos | catopen | 3c | 216 |
| netbsd | catopen | 3 | 216 |
| osx | catopen | 3 | 215 |
| opensolaris | catopen | 3c | 213 |
| xfree86 | catopen | 3 | 202 |
| posix | catopen | 3p | 179 |
| osf1 | catopen | 3 | 171 |
| suse | catopen | 3p | 115 |
| centos | catopen | 3p | 109 |