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Full Discussion: pointer to structures
Top Forums Programming pointer to structures Post 83105 by pflynn on Saturday 10th of September 2005 08:30:49 PM
Old 09-10-2005
Quote:
static struct apvt {
int dead;
int pending;
int abouttograb;
}*agents=NULL;

what agents pointer is pointing to ?
It's pointing to nothing. It's just what one call a null pointer.

Quote:
struct apvt *p;
struct apvt *newlyavailable;
if (p == newlyavailable)

actually what are we try to test with this is it mean that both have the same location or so .. ?
Yes ! You got it Smilie . It's testing if both pointers points to the same structure. If so, their contents are the same.

Quote:
struct apvt *p;
p = agents;


so now what does this p refers to ... ?
p refers to the same location as agents does, that is, p is a NULL pointer.
 

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cfengine(8)						      System Manager's Manual						       cfengine(8)

NAME
cfrun - Execute remote cfagents SYNOPSIS
/usr/sbin/cfrun [options] DESCRIPTION
cfengine is a language based system specifically designed for testing and configuring unix-like systems attached to a TCP/IP network. cfrun is a tool for executing one or more remote agents; it contacts the cfservd daemon running on a remote host, which (in turn) starts an authorized agent. Cfrun cannot be used to send instructions to a remote agent, but it can be used to flag certain aspects to the agent's existing policy for special attention.. The command line options for cfrun are slightly unusual. They are separated into three sections: options to the cfrun program, options to the remote cfagent (with some security restrictions) and finally classes or flags to the remote agent. EXAMPLES
cfrun specialhost1 specialhost2 -- --verbose -- solaris In this example, we contact hosts specialhost1 specialhost2 by name, and ask them to execute cfagent with the --verbose flag, if the class solaris is not defined. cfrun specialhost1 --verbose -- -- solaris In this example the verbose flag is sent to cfrun rather than to the remote agent. No options are sent to the remote agents. The class specifier is sent to all the agents so that they may determine whether they fulfill the required class membership for execution. The default behaviour is to execute cfagent serially on all hosts listed in the cfrun.hosts file. FILES
cfrun read a configuration file cfrun.hosts which must contain a list of every potentially contactable host. AUTHOR
Mark Burgess, Oslo University College INFORMATION
http://www.cfengine.org Maintenance Commands cfengine(8)
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