GETDTABLESIZE(2)                 System Calls                 GETDTABLESIZE(2)

NAME

       getdtablesize - get descriptor table size

SYNOPSIS

       #include <unistd.h>

       int getdtablesize(void);

DESCRIPTION

       Each  process has a fixed size descriptor table, which is guaranteed to
       have at least 20 slots.  The entries in the descriptor table  are  num‐
       bered  with  small  integers starting at 0.  The call getdtablesize re‐
       turns the size of this table.

       This call is mainly intended for use on systems which have configurable
       kernels.   Since  the GNO kernel is not yet configurable, this function
       always returns OPEN_MAX.

BUGS

       The concept of the maximum number of concurrently open files is not yet
       consistent between GS/OS, the GNO kernel, and the C library.  For exam‐
       ple, the kernel uses OPEN_MAX as the largest number of open files,  yet
       GS/OS does not have a hard upper limit.  It is recommended for now that
       the return value of getdtablesize be assumed in applications to be  the
       largest number of open files, as it is the smallest value.

SEE ALSO

       close(2), dup(2), open(2), select(2)

HISTORY

       The getdtablesize function call appeared in 4.2BSD.



GNO                            22 February 1996               GETDTABLESIZE(2)