getdtablesize

Returns the maximum number of file descriptors the calling process may open.

Prototype

int getdtablesize(void);

Returns: int

Version history

XNU tag	macOS	#
xnu-1456.1.26	macOS 10.6 Snow Leopard	89
xnu-1699.24.8	macOS 10.7 Lion	89
xnu-2050.18.24	macOS 10.8 Mountain Lion	89
xnu-2422.115.4	macOS 10.9 Mavericks	89
xnu-2782.40.9	macOS 10.10 Yosemite	89
xnu-3247.1.106	macOS 10.11 El Capitan	89
xnu-3789.1.32	macOS 10.12 Sierra	89
xnu-4570.1.46	macOS 10.13 High Sierra	89
xnu-4903.221.2	macOS 10.14 Mojave	89
xnu-6153.11.26	macOS 10.15 Catalina	89
xnu-1486.2.11	—	89
xnu-1504.15.3	—	89
xnu-1504.3.12	—	89
xnu-1504.7.4	—	89
xnu-1504.9.17	—	89
xnu-1504.9.26	—	89
xnu-1504.9.37	—	89
xnu-1699.22.73	—	89
xnu-1699.22.81	—	89
xnu-1699.24.23	—	89
xnu-1699.26.8	—	89
xnu-1699.32.7	—	89
xnu-2050.22.13	—	89
xnu-2050.24.15	—	89
xnu-2050.48.11	—	89
xnu-2050.7.9	—	89
xnu-2050.9.2	—	89
xnu-2422.1.72	—	89
xnu-2422.100.13	—	89
xnu-2422.110.17	—	89
xnu-2422.90.20	—	89
xnu-2782.1.97	—	89
xnu-2782.10.72	—	89
xnu-2782.20.48	—	89
xnu-2782.30.5	—	89
xnu-3247.10.11	—	89
xnu-3248.20.55	—	89
xnu-3248.30.4	—	89
xnu-3248.40.184	—	89
xnu-3248.50.21	—	89
xnu-3248.60.10	—	89
xnu-3789.21.4	—	89
xnu-3789.31.2	—	89
xnu-3789.41.3	—	89
xnu-3789.51.2	—	89
xnu-3789.60.24	—	89
xnu-3789.70.16	—	89
xnu-4570.20.62	—	89
xnu-4570.31.3	—	89
xnu-4570.41.2	—	89
xnu-4570.51.1	—	89
xnu-4570.61.1	—	89
xnu-4570.71.2	—	89
xnu-4903.231.4	—	89
xnu-4903.241.1	—	89
xnu-4903.270.47	—	89
xnu-6153.101.6	—	89
xnu-6153.121.1	—	89
xnu-6153.141.1	—	89
xnu-6153.41.3	—	89
xnu-6153.61.1	—	89
xnu-6153.81.5	—	89

Notes

Equivalent to getrlimit(RLIMIT_NOFILE).rlim_cur in practice on macOS. Older code uses it to size select(2) bitmasks; modern code should prefer kqueue or poll and the actual RLIMIT_NOFILE value.

Related APIs

getrlimitsetrlimitproc_rlimit_controlgetrusage