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diff --git a/man/man3/wait.html b/man/man3/wait.html new file mode 100644 index 00000000..84322bc2 --- /dev/null +++ b/man/man3/wait.html @@ -0,0 +1,170 @@ +<head> +<title>wait(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>WAIT(3)</b><td align=right><b>WAIT(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> + + await, awaitnohang, awaitfor, wait, waitnohang, waitfor, waitpid + – wait for a process to exit<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>Waitmsg* wait(void) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>Waitmsg* waitnohang(void) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>Waitmsg* waitfor(int pid) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int waitpid(void) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int await(char *s, int n) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int awaitnohang(char *s, int n) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int awaitfor(int pid, char *s, int n)<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>Wait</i> causes a process to wait for any child process (see <a href="../man2/fork.html"><i>fork</i>(2)</a> + and <a href="../man3/rfork.html"><i>rfork</i>(3)</a>) to exit. It returns a <tt><font size=+1>Waitmsg</font></tt> holding information + about the exited child. A <tt><font size=+1>Waitmsg</font></tt> has this structure:<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>typedef<br> + struct Waitmsg<br> + {<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int pid; /* of loved one */<br> + ulong time[3]; /* of loved one & descendants */<br> + char *msg;<br> + + </table> + } Waitmsg;<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + + </table> + <tt><font size=+1>Pid</font></tt> is the child’s process id. The <tt><font size=+1>time</font></tt> array contains the time + the child and its descendants spent in user code, the time spent + in system calls, and the child’s elapsed real time, all in units + of milliseconds. <tt><font size=+1>Msg</font></tt> contains the message that the child specified + in <a href="../man3/exits.html"><i>exits</i>(3)</a>. For a normal exit, <tt><font size=+1>msg[0]</font></tt> is zero, otherwise <tt><font size=+1>msg + </font></tt>is the exit string prefixed by the process name, a blank, the + process id, and a colon. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + If there are no more children to wait for, <i>wait</i> returns immediately, + with return value nil. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The <tt><font size=+1>Waitmsg</font></tt> structure is allocated by <a href="../man3/malloc.html"><i>malloc</i>(3)</a> and should be + freed after use. For programs that only need the pid of the exiting + program, <i>waitpid</i> returns just the pid and discards the rest of + the information. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Waitnohang</i> is like <i>wait</i> but does not block if there are no more + children to wait for. Instead it returns immediately and sets + <i>errstr</i>. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Waitfor</i> is like <i>wait</i> but waits for a particular <i>pid</i>. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The underlying calls are <i>await</i>, <i>awaitnohang</i>, and <i>awaitfor</i>, which + fill in the <i>n</i>-byte buffer <i>s</i> with a textual representation of the + pid, times, and exit string. There is no terminal NUL. The return + value is the length, in bytes, of the data. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The filled-in buffer may be parsed (after appending a NUL) using + <i>tokenize</i> (see <a href="../man3/getfields.html"><i>getfields</i>(3)</a>); the resulting fields are, in order, + pid, the three times, and the exit string, which will be <tt><font size=+1>''</font></tt> for + normal exit. If the representation is longer than <i>n</i> bytes, it + is truncated but, if possible, properly formatted. The information + that + does not fit in the buffer is discarded, so a subsequent call + to <i>await</i> will return the information about the next exiting child, + not the remainder of the truncated message. In other words, each + call to <i>await</i> returns the information about one child, blocking + if necessary if no child has exited. If the calling process has + no + living children, <i>await</i> returns <tt><font size=+1>−1</font></tt>.<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/wait.c + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>/usr/local/plan9/src/lib9/await.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/rfork.html"><i>rfork</i>(3)</a>, <a href="../man3/exits.html"><i>exits</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 routines set <i>errstr</i>.<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> + + To avoid name conflicts with the underlying system, <i>wait</i>, <i>waitpid</i>, + and <i>waitfor</i> are preprocessor macros defined as <i>p9wait</i>, <i>p9waitpid</i>, + and <i>p9waitfor</i>; see <a href="../man3/intro.html"><i>intro</i>(3)</a>.<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> |