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diff --git a/man/man3/open.html b/man/man3/open.html new file mode 100644 index 00000000..64f85c55 --- /dev/null +++ b/man/man3/open.html @@ -0,0 +1,130 @@ +<head> +<title>open(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>OPEN(3)</b><td align=right><b>OPEN(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> + + open, create, close – open a file for reading or writing, create + 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> + + <tt><font size=+1>#include <u.h><br> + #include <libc.h> + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int open(char *file, int omode) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int create(char *file, int omode, ulong perm) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int close(int fd)<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> + + <i>Open</i> opens the <i>file</i> for I/O and returns an associated file descriptor. + <i>Omode</i> is one of <tt><font size=+1>OREAD</font></tt>, <tt><font size=+1>OWRITE</font></tt>, <tt><font size=+1>ORDWR</font></tt>, or <tt><font size=+1>OEXEC</font></tt>, asking for permission + to read, write, read and write, or execute, respectively. In addition, + there are three values that can be ORed with the <i>omode</i>: <tt><font size=+1>OTRUNC</font></tt> + says to truncate the file to zero length + before opening it; <tt><font size=+1>OCEXEC</font></tt> says to close the file when an <a href="../man3/exec.html"><i>exec</i>(3)</a> + or <i>execl</i> system call is made; and <tt><font size=+1>ORCLOSE</font></tt> says to remove the file + when it is closed (by everyone who has a copy of the file descriptor). + <i>Open</i> fails if the file does not exist or the user does not have + permission to open it for the requested purpose (see + <a href="../man3/stat.html"><i>stat</i>(3)</a> for a description of permissions). The user must have + write permission on the <i>file</i> if the <tt><font size=+1>OTRUNC</font></tt> bit is set. For the + <i>open</i> system call (unlike the implicit <i>open</i> in <a href="../man3/exec.html"><i>exec</i>(3)</a>), <tt><font size=+1>OEXEC</font></tt> + is actually identical to <tt><font size=+1>OREAD</font></tt>. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Create</i> creates a new <i>file</i> or prepares to rewrite an existing <i>file</i>, + opens it according to <i>omode</i> (as described for <i>open</i>), and returns + an associated file descriptor. If the file is new, the owner is + set to the userid of the creating process group; the group to + that of the containing directory; the permissions to <i>perm</i> ANDed + with + the permissions of the containing directory. If the file already + exists, it is truncated to 0 length, and the permissions, owner, + and group remain unchanged. The created file is a directory if + the <tt><font size=+1>DMDIR</font></tt> bit is set in <i>perm</i>, an exclusive-use file if the <tt><font size=+1>DMEXCL</font></tt> + bit is set, and an append-only file if the <tt><font size=+1>DMAPPEND</font></tt> bit is set. + Exclusive-use files may be open for I/O by only one client at + a time, but the file descriptor may become invalid if no I/O is + done for an extended period; see <i>open</i>(9p). + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Create</i> fails if the path up to the last element of <i>file</i> cannot + be evaluated, if the user doesn’t have write permission in the + final directory, if the file already exists and does not permit + the access defined by <i>omode</i>, of if there there are no free file + descriptors. In the last case, the file may be created even when + an error is + returned. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + Since <i>create</i> may succeed even if the file exists, a special mechanism + is necessary for those applications that require an atomic create + operation. If the <tt><font size=+1>OEXCL</font></tt> (<tt><font size=+1>0x1000</font></tt>) bit is set in the <i>mode</i> for a + <i>create,</i> the call succeeds only if the file does not already exist; + see <i>open</i>(9p) for details. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Close</i> closes the file associated with a file descriptor. Provided + the file descriptor is a valid open descriptor, <i>close</i> is guaranteed + to close it; there will be no error. Files are closed automatically + upon termination of a process; <i>close</i> allows the file descriptor + to be reused.<br> + +</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/lib9<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/intro.html"><i>intro</i>(3)</a>, <a href="../man3/stat.html"><i>stat</i>(3)</a><br> + +</table> +<p><font size=+1><b>DIAGNOSTICS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + These functions set <i>errstr</i>.<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> |