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listxattr(2) [mojave man page]

LISTXATTR(2)						      BSD System Calls Manual						      LISTXATTR(2)

NAME
listxattr, flistxattr -- list extended attribute names SYNOPSIS
#include <sys/xattr.h> ssize_t listxattr(const char *path, char *namebuf, size_t size, int options); ssize_t flistxattr(int fd, char *namebuf, size_t size, int options); DESCRIPTION
Extended attributes extend the basic attributes associated with files and directories in the file system. They are stored as name:data pairs associated with file system objects (files, directories, symlinks, etc). listxattr() retrieves a list of names of extended attributes associated with the given path in the file system. namebuf is a data buffer of size bytes for the names of the extended attributes associated with path. The extended attribute names are sim- ple NULL-terminated UTF-8 strings and are returned in arbitrary order. No extra padding is provided between names in the buffer. The list will only include names of extended attributes to which the calling process has access. The function returns the size of the list of names. options controls how the attribute list is generated: XATTR_NOFOLLOW do not follow symbolic links. listxattr() normally lists attributes of the target of path if it is a symbolic link. With this option, listxattr() will list attributes of the link itself. XATTR_SHOWCOMPRESSION listxattr() and flistxattr() will list HFS Plus Compression extended attribute(s) (if present) for the file referred to by path or fd. If namebuf is set to NULL, the function returns the size of the list of extended attribute names. This facility can be used to determine the size of a buffer sufficiently large to hold the names of the attributes currently associated with path. flistxattr() is identical to listxattr(), except that it returns the list of extended attribute names associated with the open file refer- enced by file descriptor fd. RETURN VALUES
On success, the size of the extended attribute name list is returned. If no accessible extended attributes are associated with the given path or fd, the function returns zero. On failure, -1 is returned and the global variable errno is set as follows. ERRORS
[ENOTSUP] The file system does not support extended attributes or has the feature disabled. [ERANGE] namebuf (as indicated by size) is too small to hold the list of names. [EPERM] path or fd refer to a file system object that does not support extended attributes. For example, resource forks don't support extended attributes. [ENOTDIR] A component of path 's prefix is not a directory. [ENAMETOOLONG] name exceeds XATTR_MAXNAMELEN UTF-8 bytes, or a component of path exceeds NAME_MAX characters, or the entire path exceeds PATH_MAX characters. [EACCES] Search permission is denied for a component of path or permission is denied to read the list of attributes from this file. [ELOOP] Too many symbolic links were encountered resolving path. [EFAULT] path points to an invalid address. [EIO] An I/O error occurred. [EINVAL] options does not make sense. SEE ALSO
getxattr(2), removexattr(2), setxattr(2) HISTORY
listxattr() and flistxattr() first appeared in Mac OS X 10.4. Mac OS X Oct 19, 2004 Mac OS X

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REMOVEXATTR(2)						      BSD System Calls Manual						    REMOVEXATTR(2)

NAME
removexattr, fremovexattr -- remove an extended attribute value SYNOPSIS
#include <sys/xattr.h> int removexattr(const char *path, const char *name, int options); int fremovexattr(int fd, const char *name, int options); DESCRIPTION
Extended attributes extend the basic attributes associated with files and directories in the file system. They are stored as name:data pairs associated with file system objects (files, directories, symlinks, etc). removexattr() deletes the extended attribute name associated with path. An extended attribute's name is a simple NULL-terminated UTF-8 string. Options is a bit mask specifying various options: XATTR_NOFOLLOW do not follow symbolic links. Normally, removexattr() acts on the target of path if it is a symbolic link. With this option, removexattr() will act on the link itself. XATTR_SHOWCOMPRESSION removexattr() and fremovexattr() will remove HFS Plus Compression extended attribute name (if present) for the file referred to by path or fd. fremovexattr() is identical to removexattr(), except that it removes an extended attribute from an open file referenced by file descriptor fd. RETURN VALUES
On success, 0 is returned. On failure, -1 is returned and the global variable errno is set as follows. ERRORS
[ENOATTR] The specified extended attribute does not exist. [ENOTSUP] The file system does not support extended attributes or has the feature disabled. [EROFS] The file system is mounted read-only. [EPERM] This type of object does not support extended attributes. [EINVAL] name or options is invalid. name must be valid UTF-8 options must make sense. [ENOTDIR] A component of the path 's prefix is not a directory. [ENAMETOOLONG] Name exceeded XATTR_MAXNAMELEN UTF-8 bytes, or a component of path exceeded NAME_MAX characters, or the entire path exceeded PATH_MAX characters. [EACCES] Search permission is denied for a component path or permission to remove the attribute is denied. [ELOOP] Too many symbolic links were encountered in path. [EFAULT] path or name points to an invalid address. [EIO] An I/O error occurred while reading from or writing to the file system. SEE ALSO
getxattr(2), listxattr(2), setxattr(2) HISTORY
removexattr() and fremovexattr() first appeared in Mac OS X 10.4. Mac OS X Oct 19, 2004 Mac OS X

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