| OS | Man Page | Section | Hits |
|---|---|---|---|
| freebsd | catopen | 3 | 172 |
| opendarwin | catopen | 3 | 102 |
| redhat | catopen | 3 | 90 |
| linux | catopen | 3 | 80 |
| mojave | catopen | 3 | 79 |
| sunos | catopen | 3c | 73 |
| opensolaris | catopen | 3c | 72 |
| netbsd | catopen | 3 | 71 |
| v7 | catopen | 3 | 62 |
| debian | catopen | 3 | 61 |
| osf1 | catopen | 3 | 57 |
| osx | catopen | 3 | 56 |
| centos | catopen | 3 | 54 |
| ultrix | catopen | 3int | 54 |
| suse | catopen | 3 | 53 |
| hpux | catopen | 3c | 51 |
| xfree86 | catopen | 3 | 51 |
| posix | catopen | 3p | 44 |
| suse | catopen | 3p | 22 |
| centos | catopen | 3p | 16 |