problem implementing fork

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Old 10-11-2009
A couple of things come to mnd....
  1. I'd use something other than SIGALRM to signal the parent. Perhaps SIGCHLD or SIGUSR1
  2. Forking gives the parent the opportunity to do something useful if the kid hangs. For instance, if the I/O subsystem were to be unable to complete an i/o and fail to return an error on a Solaris (or any system using DMA for I/O) , the kid will be unkillable and hang. This is because you might remove the process memory, reallocate it to another process only to have the DMA device complete the physical i/o. It might be useful to tell someone about the i/o issue via a timeout mechanism.
  3. Is forking all that expensive in a Linux system? Most everything except for the LWP stuff will be created with either model. The forking model makes expansion of the code to handle multiple tasks saner..

sorry about the late reply...
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UUIDD(8)						       System Administration							  UUIDD(8)

uuidd - UUID generation daemon SYNOPSIS
uuidd [options] DESCRIPTION
The uuidd daemon is used by the UUID library to generate universally unique identifiers (UUIDs), especially time-based UUIDs, in a secure and guaranteed-unique fashion, even in the face of large numbers of threads running on different CPUs trying to grab UUIDs. OPTIONS
-d, --debug Run uuidd in debugging mode. This prevents uuidd from running as a daemon. -h, --help Display help screen and exit. -k, --kill If currently a uuidd daemon is running, kill it. -n, --uuids number When issuing a test request to a running uuidd, request a bulk response of number UUIDs. -p, --pid path Specify the pathname where the pid file should be written. By default, the pid file is written to /var/uuidd/ -P, --no-pid Do not create pid file. -F, --no-fork Do not daemonize using double-fork. -S, --socket-activation Do not create the socket and instead expect it to be provided by the calling process. Implies --no-fork and --no-pid. As of this writing, this option is supposed to be used only with systemd. This option must be enabled with a configure option. -q, --quiet Suppress some failure messages. -r, --random Test uuidd by trying to connect to a running uuidd daemon and request it to return a random-based UUID. -s, --socket path Specify the pathname used for the unix-domain socket used by uuidd. By default, the pathname used is /var/uuidd/request. This is primarily for debugging purposes, since the pathname is hard-coded in the libuuid library. -T, --timeout timeout Specify a timeout for uuidd. If specified, then uuidd will exit after timeout seconds of inactivity. -t, --time Test uuidd by trying to connect to a running uuidd daemon and request it to return a time-based UUID. -V, --version Output version information and exit. EXAMPLE
Start up a daemon, print 42 random keys, and then stop the daemon. uuidd -p /tmp/ -s /tmp/uuidd.socket uuidd -d -r -n 42 -s /tmp/uuidd.socket uuidd -d -k -s /tmp/uuidd.socket AUTHOR
The uuidd daemon was written by Theodore Ts'o <>. AVAILABILITY
The uuidd daemon is part of the util-linux package and is available from SEE ALSO
uuid(3), uuidgen(1) util-linux June 2011 UUIDD(8)