man2/getdtablesize.2

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   3 .\" Copyright 1993 Rickard E. Faith (faith@cs.unc.edu)
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  25 .\" Modified 2002-04-15 by Roger Luethi <rl@hellgate.ch> and aeb
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  27 .TH GETDTABLESIZE 2 2002-04-15 "Linux 2.4" "Linux Programmer's Manual"
  28 .SH NAME
  29 getdtablesize \- get descriptor table size
  30 .SH SYNOPSIS
  31 .B #include <unistd.h>
  32 .sp
  33 .B int getdtablesize(void);
  34 .SH DESCRIPTION
  35 .BR getdtablesize ()
  36 returns the maximum number of files a process can have open,
  37 one more than the largest possible value for a file descriptor.
  38 .SH "RETURN VALUE"
  39 The current limit on the number of open files per process.
  40 .SH NOTES
  41 .BR getdtablesize ()
  42 is implemented as a libc library function. The glibc version calls
  43 .BR getrlimit (2)
  44 and returns the current
  45 .B RLIMIT_NOFILE
  46 limit, or
  47 .B OPEN_MAX
  48 when that fails.
  49 The libc4 and libc5 versions return
  50 .B OPEN_MAX
  51 (set to 256 since Linux 0.98.4).
  52 .SH "CONFORMING TO"
  53 SVr4, 4.4BSD (the
  54 .BR getdtablesize ()
  55 function first appeared in 4.2BSD).
  56 .SH "SEE ALSO"
  57 .BR close (2),
  58 .BR dup (2),
  59 .BR getrlimit (2),
  60 .BR open (2)