| .TH ACCESS 3 | |
| .SH NAME | |
| access \- determine accessibility of file | |
| .SH SYNOPSIS | |
| .B #include <u.h> | |
| .br | |
| .B #include <libc.h> | |
| .PP | |
| .B | |
| int access(char *name, int mode) | |
| .SH DESCRIPTION | |
| .I Access | |
| evaluates the given | |
| file | |
| .I name | |
| for accessibility. | |
| If \fImode\fL&4\fR | |
| is nonzero, | |
| read permission is expected; | |
| if \fImode\fL&2\fR, | |
| write permission; | |
| if \fImode\fL&1\fR, | |
| execute permission. | |
| If \fImode\fL==0\fR, | |
| the file merely need exist. | |
| In any case | |
| all directories leading to the file | |
| must permit searches. | |
| Zero is returned if the desired access is permitted, | |
| \-1 if not. | |
| .PP | |
| Only access for open is checked. | |
| A file may look executable, but | |
| .IR exec (3) | |
| will fail unless it is in proper format. | |
| .PP | |
| The include file | |
| .F <libc.h> | |
| defines | |
| .BR AEXIST =0, | |
| .BR AEXEC =1, | |
| .BR AWRITE =2, | |
| and | |
| .BR AREAD =4. | |
| .PP | |
| .SH SOURCE | |
| .B /usr/local/plan9/src/libc/9sys/access.c | |
| .SH SEE ALSO | |
| .IR stat (3) | |
| .SH DIAGNOSTICS | |
| Sets | |
| .IR errstr . | |
| .SH BUGS | |
| Since file permissions are checked by the server and group information | |
| is not known to the client, | |
| .I access | |
| must open the file to check permissions. | |
| (It calls | |
| .IR stat (3) | |
| to check simple existence.) |