NAME

access − determine accessibility of a file

SYNOPSIS

#include <unistd.h>

int access(const char ∗path, int amode);

MT-LEVEL

Async-Signal-Safe

DESCRIPTION

access() checks the file pointed to by path for accessibility according to the bit pattern contained in amode, using the real user ID in place of the effective user ID and the real group ID in place of the effective group ID.  This allows a setuid process to verify that the user running it would have had permission to access this file.  The bit pattern contained in amode is constructed by an OR of the access permissions to be checked (R_OK, W_OK, and X_OK, or the existence test, (F_OK).  These constants are defined in <unistd.h> as follows:

R_OKTest for read permission. 
W_OKTest for write permission. 
X_OKTest for execute or search permission. 
F_OKCheck existence of file

See intro(2) for additional information about "File Access Permission". 

RETURN VALUES

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

ERRORS

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

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. 

EFAULT path points to an illegal address. 

EINTR A signal was caught during the access() function. 

ELOOP Too many symbolic links were encountered in translating path.

EMULTIHOP Components of path require hopping to multiple remote machines. 

ENAMETOOLONG The length of the path argument exceeds {PATH_MAX}, or the length of a path component exceeds {NAME_MAX} while {_POSIX_NO_TRUNC} is in effect. 

ENOENT The path argument points to an empty string or to the name of a file that does not exist. 

ENOLINK path points to a remote machine and the link to that machine is no longer active. 

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

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

SEE ALSO

intro(2), chmod(2), stat(2)

SunOS 5.5/SPARC  —  Last change: 29 Jul 1991