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     44 <h1>Reimplementing <code>sysmgr</code> in C</h1>
     45 
     46 <p>For a while, I have been thinking about implementing <a href="https://git.ckyln.com/sysmgr">sysmgr</a> in C. I started
     47 thinking about the inefficiencies of sysmgr. POSIX sh isn&rsquo;t particularly
     48 designed to have ultimate control over child processes. There are basic job
     49 management features that are <em>just enough</em> for sysmgr to do its job. The
     50 biggest pain is having to use tools like <code>sleep(1)</code> and <code>kill(1)</code>. Calling
     51 sleep every second, and using the kill command to check whether a process is
     52 alive or not is extremely inefficient. Some shells <em>do</em> include these commands
     53 built-in, but it isn&rsquo;t specified by POSIX, but one should never take this as
     54 granted.</p>
     55 
     56 <p>Lately, I have been adding C utilities to sysmgr to make it more efficient. This
     57 defeats the initial purpose of sysmgr, being a service manager in pure POSIX
     58 shell. My main purpose, however, is making sysmgr efficient and simplistic. It
     59 mostly imitates <code>runit</code> without dealing with all the complexity of the
     60 over-thinked <code>supervise</code> directory, nor the logging stuff. Most of these can be
     61 handled by the service script itself anyway. That&rsquo;s why instead of this ugly
     62 C/POSIX sh hybrid, I decided to implement it all in C.</p>
     63 
     64 <p>I am not a C expert or anything, I am learning a lot as I am writing the
     65 program. I want it to be C99 and portable (for BSD). It&rsquo;s currently not
     66 functional at all, but, you can see its current state <a href="https://git.ckyln.com/sm">here</a>.</p>
     67 
     68 <p>EDIT Oct 10 2020:</p>
     69 
     70 <p>I did the initial release of this C version of sysmgr, which is more stable,
     71 and performant than the POSIX sh version. It still has rough edges, but is
     72 completely usable.</p>
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