GETDTABLESIZE(3) NetBSD Library Functions Manual GETDTABLESIZE(3)
getdtablesize -- get descriptor table size
Standard C Library (libc, -lc)
#include <unistd.h> int getdtablesize(void);
The getdtablesize function is an equivalent of sysconf() with _SC_OPEN_MAX.
close(2), dup(2), getrlimit(2), open(2), select(2), sysconf(3)
The getdtablesize() function call appeared in 4.2BSD. Historically, each process had a fixed size descriptor table, which is guaranteed to have at least 20 slots. The entries in the descriptor ta- ble are numbered with small integers starting at 0. The call getdtablesize() used to return the size of this table. It doesn't make much sense these days because the size of the table is dynamic. NetBSD 9.0 January 5, 2012 NetBSD 9.0
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