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diff --git a/man/man9/read.html b/man/man9/read.html new file mode 100644 index 00000000..c524d8de --- /dev/null +++ b/man/man9/read.html @@ -0,0 +1,96 @@ +<head> +<title>read(9P) - 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>READ(9P)</b><td align=right><b>READ(9P)</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> + + read, write – transfer data from and to a file<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> + + <i>size</i>[4] <tt><font size=+1>Tread</font></tt> <i>tag</i>[2] <i>fid</i>[4] <i>offset</i>[8] <i>count</i>[4]<br> + <i>size</i>[4] <tt><font size=+1>Rread</font></tt> <i>tag</i>[2] <i>count</i>[4] <i>data</i>[<i>count</i>] + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>size</i>[4] <tt><font size=+1>Twrite</font></tt> <i>tag</i>[2] <i>fid</i>[4] <i>offset</i>[8] <i>count</i>[4] <i>data</i>[<i>count</i>]<br> + <i>size</i>[4] <tt><font size=+1>Rwrite</font></tt> <i>tag</i>[2] <i>count</i>[4]<br> + +</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> + + The <tt><font size=+1>read</font></tt> request asks for <i>count</i> bytes of data from the file identified + by <i>fid</i>, which must be opened for reading, starting <i>offset</i> bytes + after the beginning of the file. The bytes are returned with the + <tt><font size=+1>read</font></tt> reply message. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The <i>count</i> field in the reply indicates the number of bytes returned. + This may be less than the requested amount. If the <i>offset</i> field + is greater than or equal to the number of bytes in the file, a + count of zero will be returned. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + For directories, <tt><font size=+1>read</font></tt> returns an integral number of directory + entries exactly as in <tt><font size=+1>stat</font></tt> (see <i>stat</i>(9P)), one for each member + of the directory. The <tt><font size=+1>read</font></tt> request message must have <tt><font size=+1>offset</font></tt> equal + to zero or the value of <tt><font size=+1>offset</font></tt> in the previous <tt><font size=+1>read</font></tt> on the directory, + plus the number of bytes returned in the previous + <tt><font size=+1>read</font></tt>. In other words, seeking other than to the beginning is illegal + in a directory. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The <tt><font size=+1>write</font></tt> request asks that <i>count</i> bytes of data be recorded in + the file identified by <i>fid</i>, which must be opened for writing, + starting <i>offset</i> bytes after the beginning of the file. If the + file is append-only, the data will be placed at the end of the + file regardless of <i>offset</i>. Directories may not be written. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The <tt><font size=+1>write</font></tt> reply records the number of bytes actually written. + It is usually an error if this is not the same as requested. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + Because 9P implementations may limit the size of individual messages, + more than one message may be produced by a single <i>read</i> or <i>write</i> + call. The <i>iounit</i> field returned by <i>open</i>(9P), if non-zero, reports + the maximum size that is guaranteed to be transferred atomically.<br> + +</table> +<p><font size=+1><b>ENTRY POINTS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Fsread</i> and <i>fswrite</i> (see <a href="../man3/9pclient.html"><i>9pclient</i>(3)</a>) generate the corresponding + messages. Because they take an offset parameter, the <i>fspread</i> and + <i>fspwrite</i> calls correspond more directly to the 9P messages. Although + <i>fsseek</i> affects the offset, it does not generate a message.<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> |