gno/usr.man/man2/access.2
1997-02-27 07:32:31 +00:00

92 lines
2.3 KiB
Groff

.\"
.\" Devin Reade, 1995
.\"
.\" $Id: access.2,v 1.1 1997/02/27 07:32:11 gdr Exp $
.\"
.TH ACCESS 2 "16 January 1997" GNO "System Calls"
.SH NAME
access \- determine accessibility of file
.SH SYNOPSIS
#include <unistd.h>
.sp 1
int
\fBaccess\fR (const char *\fIpath\fR, int \fImode\fR);
.SH DESCRIPTION
.I path
points to a path name naming a file.
.B access(\|)
checks the named file
for accessibility according to
.IR mode ,
which is an inclusive or of the following bits:
.RS
.IP \fBR_OK\fR
Test for read permission.
.IP \fBW_OK\fR
Test for write permission. Under GNO, a file must have all three of
its GS/OS write, rename, and destroy bits set to be considered writable.
.IP \fBX_OK\fR
Test for execute or search permission. Under GNO, the test will pass if
the file is of type EXE, S16, a directory, or of type SRC with an EXEC
auxiliary type.
.RE
.LP
The following value may also be supplied for
.IR mode :
.RS
.IP \fBF_OK\fR
test whether the directories leading to the file can be searched and the file exists.
.RE
.LP
Notice that only access bits are checked. A directory may be indicated as writable by
.BR access(\|) ,
but an attempt to open it for writing will fail
(although files may be created there); a file may look executable, but
.B execve(\|)
will fail unless it is in proper format.
.SH RETURN VALUES
.B access(\|)
returns zero on success. On failure it returns -1 and sets
.BR errno .
.SH ERRORS
.IP EACCES
Search permission is denied for a component of the path prefix of
.IR path .
.sp 1
The file access permissions do not permit the requested
access to the file named by
.IR path .
.IP EFAULT
.I path
points outside the process's allocated address space.
.IP EINVAL
An invalid value was specified for
.IR mode .
.sp 1
The length of the path argument exceeds
.BR FILENAME_MAX .
.IP EIO
An I/O error occurred while reading from or writing to the file system.
.IP ELOOP
Too many symbolic links were encountered in translating
.IR path .
(Not currently possible under GNO.)
.IP ENOENT
The file named by
.I path
does not exist.
.IP ENOTDIR
A component of the path prefix of
.I path
is not a directory.
.SH SYSTEM V ERRORS
In addtion to the above, the following may also occur:
.IP ENOENT
.I path
points to an empty string.
.SH BUGS
Nothing special is done for the AppleShare FST.
.SH "SEE ALSO"
.BR chmod (2V),
.BR stat (2V)