getdtablesize(2)getdtablesize(2)NAMEgetdtablesize - Get the size of the descriptor table
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
getdtablesize(): XSH4.2, XSH5.0
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
The getdtablesize() function returns the maximum number of file
descriptors in a process' descriptor table. Each process has a fixed
size descriptor table that is guaranteed to have at least 64 slots.
The entries in the descriptor table are numbered with small integers
starting at 0 (zero).
The getdtablesize() function returns the total number of file descrip‐
tors that a process can have open simultaneously. Each process is lim‐
ited to a fixed number of open file descriptors. This limit is at least
64. The system-defined limit is configurable. If it is greater than 64,
the system will allocate more file descriptors for a process up to the
defined maximum. See the descriptions of the open_max_hard and
open_max_soft attributes in sys_attrs_proc(5) for information about
changing the per-process limit on open file descriptors.
The getdtablesize() function returns the size of the descriptor table,
and is always successful.
Functions: close(2), getrlimit(2), open(2), select(2)