fdopendir(3)


NAME

   opendir, fdopendir - open a directory

SYNOPSIS

   #include <sys/types.h>
   #include <dirent.h>

   DIR *opendir(const char *name);
   DIR *fdopendir(int fd);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

   fdopendir():
       Since glibc 2.10:
           _POSIX_C_SOURCE >= 200809L
       Before glibc 2.10:
           _GNU_SOURCE

DESCRIPTION

   The  opendir()  function  opens a directory stream corresponding to the
   directory name, and returns a pointer to  the  directory  stream.   The
   stream is positioned at the first entry in the directory.

   The  fdopendir()  function  is  like opendir(), but returns a directory
   stream for the directory referred to by the open  file  descriptor  fd.
   After  a  successful  call to fdopendir(), fd is used internally by the
   implementation, and should not otherwise be used by the application.

RETURN VALUE

   The opendir()  and  fdopendir()  functions  return  a  pointer  to  the
   directory  stream.   On  error,  NULL  is  returned,  and  errno is set
   appropriately.

ERRORS

   EACCES Permission denied.

   EBADF  fd is not a valid file descriptor opened for reading.

   EMFILE The per-process limit on the number of open file descriptors has
          been reached.

   ENFILE The system-wide limit on the total number of open files has been
          reached.

   ENOENT Directory does not exist, or name is an empty string.

   ENOMEM Insufficient memory to complete the operation.

   ENOTDIR
          name is not a directory.

VERSIONS

   fdopendir() is available in glibc since version 2.4.

ATTRIBUTES

   For  an  explanation  of  the  terms  used   in   this   section,   see
   attributes(7).

   
   Interface               Attribute      Value   
   
   opendir(), fdopendir()  Thread safety  MT-Safe 
   

CONFORMING TO

   opendir()  is  present  on SVr4, 4.3BSD, and specified in POSIX.1-2001.
   fdopendir() is specified in POSIX.1-2008.

NOTES

   Filename entries can be read from a directory stream using readdir(3).

   The underlying file descriptor of the directory stream can be  obtained
   using dirfd(3).

   The  opendir()  function  sets  the  close-on-exec  flag  for  the file
   descriptor underlying the DIR *.  The fdopendir() function  leaves  the
   setting  of  the  close-on-exec flag unchanged for the file descriptor,
   fd.  POSIX.1-200x leaves it unspecified whether a  successful  call  to
   fdopendir()  will  set  the close-on-exec flag for the file descriptor,
   fd.

SEE ALSO

   open(2), closedir(3), dirfd(3), readdir(3),  rewinddir(3),  scandir(3),
   seekdir(3), telldir(3)

COLOPHON

   This  page  is  part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs,  and  the
   latest     version     of     this    page,    can    be    found    at
   https://www.kernel.org/doc/man-pages/.





Opportunity


Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.

Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.





Free Software


Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.


Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.





Free Books


The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.


Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.





Education


Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.


Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.