creat(2) [minix man page]
CREAT(2) System Calls Manual CREAT(2) NAME
creat - create a new file SYNOPSIS
#include <sys/types.h> #include <fcntl.h> int creat(const char *name, mode_t mode) DESCRIPTION
This interface is made obsolete by open(2), it is equivalent to open(name, O_WRONLY | O_CREAT | O_TRUNC, mode) Creat creates a new file or prepares to rewrite an existing file called name, given as the address of a null-terminated string. If the file did not exist, it is given mode mode, as modified by the process's mode mask (see umask(2)). Also see chmod(2) for the construction of the mode argument. If the file did exist, its mode and owner remain unchanged but it is truncated to 0 length. The file is also opened for writing, and its file descriptor is returned. NOTES
The mode given is arbitrary; it need not allow writing. This feature has been used in the past by programs to construct a simple, exclu- sive locking mechanism. It is replaced by the O_EXCL open mode, or the advisory locking of the fcntl(2) facility. RETURN VALUE
The value -1 is returned if an error occurs. Otherwise, the call returns a non-negative descriptor that only permits writing. ERRORS
Creat will fail and the file will not be created or truncated if one of the following occur: [ENOTDIR] A component of the path prefix is not a directory. [ENAMETOOLONG] The path name exceeds PATH_MAX characters. [ENOENT] The named file does not exist. [ELOOP] Too many symbolic links were encountered in translating the pathname. (Minix-vmd) [EACCES] Search permission is denied for a component of the path prefix. [EACCES] The file does not exist and the directory in which it is to be created is not writable. [EACCES] The file exists, but it is unwritable. [EISDIR] The file is a directory. [EMFILE] There are already too many files open. [ENFILE] The system file table is full. [ENOSPC] The directory in which the entry for the new file is being placed cannot be extended because there is no space left on the file system containing the directory. [ENOSPC] There are no free inodes on the file system on which the file is being created. [EROFS] The named file resides on a read-only file system. [ENXIO] The file is a character special or block special file, and the associated device does not exist. [EIO] An I/O error occurred while making the directory entry or allocating the inode. [EFAULT] Name points outside the process's allocated address space. SEE ALSO
open(2), write(2), close(2), chmod(2), umask(2). 4th Berkeley Distribution May 22, 1986 CREAT(2)
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MKNOD(2) System Calls Manual MKNOD(2) NAME
mknod, mkfifo - make a special file SYNOPSIS
#include <sys/types.h> #include <unistd.h> #include <sys/stat.h> int mknod(const char *path, mode_t mode, dev_t dev) int mkfifo(const char *path, mode_t mode) DESCRIPTION
Mknod creates a new file whose name is path. The mode of the new file (including special file bits) is initialized from mode, as defined in <sys/stat.h>. (The protection part of the mode is modified by the process's mode mask (see umask(2))). The first block pointer of the i-node is initialized from dev and is used to specify which device the special file refers to. If mode indicates a block or character special file, dev is the device number of a character or block I/O device. The low eight bits of the device number hold the minor device number that selects a device among the devices governed by the same driver. The driver is selected by the major device number, the next eight bits of the device number. If mode does not indicate a block special or character special device, dev is ignored. (For example, when creating a ``fifo'' special file.) Mknod may be invoked only by the super-user, unless it is being used to create a fifo. The call mkfifo(path, mode) is equivalent to mknod(path, (mode & 0777) | S_IFIFO, 0) RETURN VALUE
Upon successful completion a value of 0 is returned. Otherwise, a value of -1 is returned and errno is set to indicate the error. ERRORS
Mknod will fail and the file mode will be unchanged if: [ENOTDIR] A component of the path prefix is not a directory. [ENAMETOOLONG] The path name exceeds PATH_MAX characters. [ENOENT] A component of the path prefix does not exist. [EACCES] Search permission is denied for a component of the path prefix. [ELOOP] Too many symbolic links were encountered in translating the pathname. (Minix-vmd) [EPERM] The process's effective user ID is not super-user. [EIO] An I/O error occurred while making the directory entry or allocating the inode. [ENOSPC] The directory in which the entry for the new node is being placed cannot be extended because there is no space left on the file system containing the directory. [ENOSPC] There are no free inodes on the file system on which the node is being created. [EROFS] The named file resides on a read-only file system. [EEXIST] The named file exists. [EFAULT] Path points outside the process's allocated address space. SEE ALSO
chmod(2), stat(2), umask(2). 4th Berkeley Distribution May 23, 1986 MKNOD(2)