| <html lang="en"> |
| <head> |
| <title>Making Special Files - The GNU C Library</title> |
| <meta http-equiv="Content-Type" content="text/html"> |
| <meta name="description" content="The GNU C Library"> |
| <meta name="generator" content="makeinfo 4.13"> |
| <link title="Top" rel="start" href="index.html#Top"> |
| <link rel="up" href="File-System-Interface.html#File-System-Interface" title="File System Interface"> |
| <link rel="prev" href="File-Attributes.html#File-Attributes" title="File Attributes"> |
| <link rel="next" href="Temporary-Files.html#Temporary-Files" title="Temporary Files"> |
| <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> |
| <!-- |
| This file documents the GNU C library. |
| |
| This is Edition 0.12, last updated 2007-10-27, |
| of `The GNU C Library Reference Manual', for version |
| 2.8 (Sourcery G++ Lite 2011.03-41). |
| |
| Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2001, 2002, |
| 2003, 2007, 2008, 2010 Free Software Foundation, Inc. |
| |
| Permission is granted to copy, distribute and/or modify this document |
| under the terms of the GNU Free Documentation License, Version 1.3 or |
| any later version published by the Free Software Foundation; with the |
| Invariant Sections being ``Free Software Needs Free Documentation'' |
| and ``GNU Lesser General Public License'', the Front-Cover texts being |
| ``A GNU Manual'', and with the Back-Cover Texts as in (a) below. A |
| copy of the license is included in the section entitled "GNU Free |
| Documentation License". |
| |
| (a) The FSF's Back-Cover Text is: ``You have the freedom to |
| copy and modify this GNU manual. Buying copies from the FSF |
| supports it in developing GNU and promoting software freedom.''--> |
| <meta http-equiv="Content-Style-Type" content="text/css"> |
| <style type="text/css"><!-- |
| pre.display { font-family:inherit } |
| pre.format { font-family:inherit } |
| pre.smalldisplay { font-family:inherit; font-size:smaller } |
| pre.smallformat { font-family:inherit; font-size:smaller } |
| pre.smallexample { font-size:smaller } |
| pre.smalllisp { font-size:smaller } |
| span.sc { font-variant:small-caps } |
| span.roman { font-family:serif; font-weight:normal; } |
| span.sansserif { font-family:sans-serif; font-weight:normal; } |
| --></style> |
| <link rel="stylesheet" type="text/css" href="../cs.css"> |
| </head> |
| <body> |
| <div class="node"> |
| <a name="Making-Special-Files"></a> |
| <p> |
| Next: <a rel="next" accesskey="n" href="Temporary-Files.html#Temporary-Files">Temporary Files</a>, |
| Previous: <a rel="previous" accesskey="p" href="File-Attributes.html#File-Attributes">File Attributes</a>, |
| Up: <a rel="up" accesskey="u" href="File-System-Interface.html#File-System-Interface">File System Interface</a> |
| <hr> |
| </div> |
| |
| <h3 class="section">14.10 Making Special Files</h3> |
| |
| <p><a name="index-creating-special-files-1596"></a><a name="index-special-files-1597"></a> |
| The <code>mknod</code> function is the primitive for making special files, |
| such as files that correspond to devices. The GNU library includes |
| this function for compatibility with BSD. |
| |
| <p>The prototype for <code>mknod</code> is declared in <samp><span class="file">sys/stat.h</span></samp>. |
| <a name="index-sys_002fstat_002eh-1598"></a> |
| <!-- sys/stat.h --> |
| <!-- BSD --> |
| |
| <div class="defun"> |
| — Function: int <b>mknod</b> (<var>const char *filename, int mode, int dev</var>)<var><a name="index-mknod-1599"></a></var><br> |
| <blockquote><p>The <code>mknod</code> function makes a special file with name <var>filename</var>. |
| The <var>mode</var> specifies the mode of the file, and may include the various |
| special file bits, such as <code>S_IFCHR</code> (for a character special file) |
| or <code>S_IFBLK</code> (for a block special file). See <a href="Testing-File-Type.html#Testing-File-Type">Testing File Type</a>. |
| |
| <p>The <var>dev</var> argument specifies which device the special file refers to. |
| Its exact interpretation depends on the kind of special file being created. |
| |
| <p>The return value is <code>0</code> on success and <code>-1</code> on error. In addition |
| to the usual file name errors (see <a href="File-Name-Errors.html#File-Name-Errors">File Name Errors</a>), the |
| following <code>errno</code> error conditions are defined for this function: |
| |
| <dl> |
| <dt><code>EPERM</code><dd>The calling process is not privileged. Only the superuser can create |
| special files. |
| |
| <br><dt><code>ENOSPC</code><dd>The directory or file system that would contain the new file is full |
| and cannot be extended. |
| |
| <br><dt><code>EROFS</code><dd>The directory containing the new file can't be modified because it's on |
| a read-only file system. |
| |
| <br><dt><code>EEXIST</code><dd>There is already a file named <var>filename</var>. If you want to replace |
| this file, you must remove the old file explicitly first. |
| </dl> |
| </p></blockquote></div> |
| |
| </body></html> |
| |