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chmod, fchmod

statx, fstatx, stat, fstat, fullstat, ffullstat, lstat



ACCESS(2,L)                 AIX Technical Reference                 ACCESS(2,L)



-------------------------------------------------------------------------------
access



PURPOSE

Determines the accessibility of a file.

SYNTAX

#include <unistd.h>

int access (path, amode)
char *path;
int amode;

DESCRIPTION

The access system call checks the accessibility of the file specified by the
path parameter. If path refers to a symbolic link, the access system call
returns information about the file pointed to by the symbolic link.

Access permission to all components of the path parameter is determined by
using the real user ID instead of the effective user ID and the concurrent
group set (without the effective group ID) along with the real group ID.

The bit pattern contained in amode is constructed by logically ORing the
following values:

   R_OK    Checks read permission.
   W_OK    Checks write permission.
   X_OK    Checks execute (search) permission.
   F_OK    Checks to see if the file exists.

The owner of a file has access checked with respect to the owner read, write,
and execute mode bits.  Members of the file's group other than the owner have
access checked with respect to the group mode bits.  All others have access
checked with respect to the other mode bits.

RETURN VALUE

If the requested access is permitted, a value of 0 is returned.  If the
requested access is denied, a value of -1 is returned and errno is set to
indicate the error.

ERROR CONDITIONS

Access to the file is denied if one or more of the following are true:

ENOTDIR   A component of the path prefix is not a directory.




Processed November 7, 1990        ACCESS(2,L)                                 1





ACCESS(2,L)                 AIX Technical Reference                 ACCESS(2,L)



ENOENT    Read, write, or execute (search) permission is requested for a null
          path name.

ENOENT    The named file does not exist.

EACCES    Search permission is denied on a component of the path prefix.

EACCES    Permission bits of the file mode do not permit the requested access.

EROFS     Write access is requested for a file on a read-only file system.

ETXTBSY   Write access is requested for a pure procedure (shared text) file
          that is being executed.

EFAULT    The path parameter points to a location outside of the process's
          allocated address space.

ESTALE    The process's root or current directory is located in an NFS virtual
          file system that has been unmounted.

ENAMETOOLONG
          A component of the path parameter exceeded NAME_MAX characters or the
          entire path parameter exceeded PATH_MAX characters.

ENOENT    A hidden directory was named, but no component inside it matched the
          process's current site path list.

ENOENT    A symbolic link was named, but the file to which it refers does not
          exist.

ELOOP     A loop of symbolic links was detected.

ENFILE    The system inode table is full.

If the Transparent Computing Facility is installed on your system, access can
also fail if one or more of the following are true:

ESITEDN1  path cannot be accessed because a site went down.

ESITEDN2  The operation was terminated because a site failed.

ENOSTORE  path is a name relative to the working directory, but no site which
          stores this directory is currently up.

ENOSTORE  A component of path is replicated but is not stored on any site which
          is currently up.

EROFS     Write access is requested for a file on a replicated file system in
          which the primary copy is unavailable.

EINTR     A signal was caught during the access system call.  This can occur if
          the internal open of this file is suspended during topology change.



Processed November 7, 1990        ACCESS(2,L)                                 2





ACCESS(2,L)                 AIX Technical Reference                 ACCESS(2,L)




RELATED INFORMATION

In this book:  "chmod, fchmod" and "statx, fstatx, stat, fstat, fullstat,
ffullstat, lstat."


















































Processed November 7, 1990        ACCESS(2,L)                                 3



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