1LAM_RTRSTORE(2) LAM REMOTE LIBRARY LAM_RTRSTORE(2)
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6 lam_rtrstore - Store LAM trace data.
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9 int lam_rtrstore (int node, int list, char *buffer, int length);
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12 The client function, lam_rtrstore(), delivers trace data from a local
13 buffer to the trace daemon. In theory, the trace transport system can
14 be used for any random data. In practice, it is used to move trace
15 data between the monitored processes and a trace visualization system.
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17 Any process can transfer trace data at any time and any number of
18 times. In theory, the trace daemon on any node can be used. In prac‐
19 tise, always use the local trace daemon, and set the node argument to
20 LOCAL.
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22 Traces are organized within the daemon in lists. The list argument
23 selects the list. This enables trace readers to selectively read trace
24 data. Trace data is read out of the daemon with rtrget(2) and related
25 functions.
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27 Any length of buffer is accepted and lam_rtrstore() will send messages
28 to the trace daemon in MAXNMSGLEN (the network packet size) byte pack‐
29 ets.
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31 The trace daemon will accept trace data and store it until the total
32 currently stored exceeds a pre-compiled maximum. At that point, if an
33 existing list with a positive number is selected, oldest traces are
34 dropped. If a new list with a positive number is selected, the current
35 traces are ignored and lam_rtrstore() has no effect.
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38 By packetizing a large buffer in smaller messages, the trace daemon
39 remains totally stateless but daemon requests from other sources may be
40 interspersed between the packets. To be completely safe, a trace
41 record should not span a MAXNMSGLEN boundary in the trace buffer.
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44 lam_rtrget(2)
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48LAM 7.1.2 March, 2006 LAM_RTRSTORE(2)