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diff --git a/man/man3/9p-file.html b/man/man3/9p-file.html deleted file mode 100644 index 63ae5042..00000000 --- a/man/man3/9p-file.html +++ /dev/null @@ -1,258 +0,0 @@ -<head> -<title>9p-file(3) - Plan 9 from User Space</title> -<meta content="text/html; charset=utf-8" http-equiv=Content-Type> -</head> -<body bgcolor=#ffffff> -<table border=0 cellpadding=0 cellspacing=0 width=100%> -<tr height=10><td> -<tr><td width=20><td> -<tr><td width=20><td><b>9P-FILE(3)</b><td align=right><b>9P-FILE(3)</b> -<tr><td width=20><td colspan=2> - <br> -<p><font size=+1><b>NAME </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - Tree, alloctree, freetree, File, createfile, closefile, removefile, - walkfile, opendirfile, readdirfile, closedirfile, hasperm – in-memory - file hierarchy<br> - -</table> -<p><font size=+1><b>SYNOPSIS </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>#include <u.h><br> - #include <libc.h><br> - #include <fcall.h><br> - #include <thread.h><br> - #include <9p.h><br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - typedef struct File<br> - {<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - Ref;<br> - Dir;<br> - void*aux;<br> - - </table> - - </table> - </font></tt> - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <i>...<br> - </i> - </table> - - </table> - <tt><font size=+1>} File;<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - typedef struct Tree<br> - {<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - File *root;<br> - - </table> - - </table> - </font></tt> - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <i>...<br> - </i> - </table> - - </table> - <tt><font size=+1>} Tree;<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - Tree* alloctree(char *uid, char *gid, ulong mode,<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - void (*destroy)(File*))<br> - - </table> - - </table> - void freetree(Tree *tree)<br> - File* createfile(File *dir, char *name, char *uid,<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - ulong mode, void *aux)<br> - - </table> - - </table> - int removefile(File *file)<br> - void closefile(File *file)<br> - File* walkfile(File *dir, char *path)<br> - Readdir* opendirfile(File *dir)<br> - long readdirfile(Readdir *rdir, char *buf, long n)<br> - void closedirfile(Readdir *rdir)<br> - int hasperm(File *file, char *uid, int p)<br> - </font></tt> -</table> -<p><font size=+1><b>DESCRIPTION </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>File</font></tt>s and <tt><font size=+1>Tree</font></tt>s provide an in-memory file hierarchy intended for - use in 9P file servers. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Alloctree</i> creates a new tree of files, and <i>freetree</i> destroys it. - The root of the tree (also the <tt><font size=+1>root</font></tt> element in the structure) - will have mode <i>mode</i> and be owned by user <i>uid</i> and group <i>gid</i>. <i>Destroy</i> - is used when freeing <tt><font size=+1>File</font></tt> structures and is described later. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <tt><font size=+1>File</font></tt>s (including directories) other than the root are created - using <i>createfile</i>, which attempts to create a file named <i>name</i> in - the directory <i>dir</i>. If created, the file will have owner <i>uid</i> and - have a group inherited from the directory. <i>Mode</i> and the permissions - of <i>dir</i> are used to calculate the permission bits for the file - as - described in <i>open</i>(9p). It is permissible for <i>name</i> to be a slash-separated - path rather than a single element. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Removefile</i> removes a file from the file tree. The file will not - be freed until the last reference to it has been removed. Directories - may only be removed when empty. <i>Removefile</i> returns zero on success, - –1 on error. It is correct to consider <i>removefile</i> to be <i>closefile</i> - with the side effect of removing the file when possible. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Walkfile</i> evaluates <i>path</i> relative to the directory <i>dir</i>, returning - the resulting file, or zero if the named file or any intermediate - element does not exist. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - The <tt><font size=+1>File</font></tt> structure’s <tt><font size=+1>aux</font></tt> pointer may be used by the client for - per-<tt><font size=+1>File</font></tt> storage. <tt><font size=+1>File</font></tt>s are reference-counted: if not zero, <i>destroy</i> - (specified in the call to <i>alloctree</i>) will be called for each file - when its last reference is removed or when the tree is freed. - <i>Destroy</i> should take care of any necessary cleanup related to - <tt><font size=+1>aux</font></tt>. When creating new file references by copying pointers, call - <i>incref</i> (see <a href="../man3/lock.html"><i>lock</i>(3)</a>) to update the reference count. To note the - removal of a reference to a file, call <i>closefile</i>. <i>Createfile</i> and - <i>walkfile</i> return new references. <i>Removefile</i>, <i>closefile</i>, and <i>walkfile</i> - (but not <i>createfile</i>) consume the passed reference. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - Directories may be read, yielding a directory entry structure - (see <i>stat</i>(9p)) for each file in the directory. In order to allow - concurrent reading of directories, clients must obtain a <tt><font size=+1>Readdir</font></tt> - structure by calling <i>opendirfile</i> on a directory. Subsequent calls - to <i>readdirfile</i> will each yield an integral number of machine- - independent stat buffers, until end of directory. When finished, - call <i>closedirfile</i> to free the <tt><font size=+1>Readdir</font></tt>. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Hasperm</i> does simplistic permission checking; it assumes only one-user - groups named by uid and returns non-zero if <i>uid</i> has permission - <i>p</i> (a bitwise-or of <tt><font size=+1>AREAD</font></tt>, <tt><font size=+1>AWRITE</font></tt> and <tt><font size=+1>AEXEC</font></tt>) according to <i>file</i><tt><font size=+1>−>mode</font></tt>. - 9P servers written using <tt><font size=+1>File</font></tt> trees will do standard permission - checks automatically; <i>hasperm</i> may be - called explicitly to do additional checks. A 9P server may link - against a different <i>hasperm</i> implementation to provide more complex - groups.<br> - -</table> -<p><font size=+1><b>EXAMPLE </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - The following code correctly handles references when elementwise - walking a path and creating a file.<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>f = tree−>root;<br> - incref(f);<br> - for(i=0; i<n && f!=nil; i++)<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - f = walkfile(f, elem[i]);<br> - - </table> - if(f == nil)<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - return nil;<br> - - </table> - nf = createfile(f, "foo", "nls", 0666, nil);<br> - closefile(f);<br> - return nf;<br> - </font></tt> - </table> - -</table> -<p><font size=+1><b>SOURCE </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>/usr/local/plan9/src/lib9p/file.c<br> - </font></tt> -</table> -<p><font size=+1><b>SEE ALSO </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <a href="../man3/9p.html"><i>9p</i>(3)</a><br> - -</table> -<p><font size=+1><b>BUGS </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - The reference counting is cumbersome.<br> - -</table> - -<td width=20> -<tr height=20><td> -</table> -<!-- TRAILER --> -<table border=0 cellpadding=0 cellspacing=0 width=100%> -<tr height=15><td width=10><td><td width=10> -<tr><td><td> -<center> -<a href="../../"><img src="../../dist/spaceglenda100.png" alt="Space Glenda" border=1></a> -</center> -</table> -<!-- TRAILER --> -</body></html> |