<div dir="ltr">If BLOCKSIZE is less than 512, X will be 0<br><div class="gmail_extra"><br><div class="gmail_quote">On Fri, Oct 17, 2014 at 10:45 PM, Jan Schaumann <span dir="ltr"><<a href="mailto:jschauma@stevens.edu" target="_blank">jschauma@stevens.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">zding4 <<a href="mailto:zding4@stevens.edu">zding4@stevens.edu</a>> wrote:<br>
> APUE book have the paragraph about st_blocks<br>
><br>
> "Be aware that different versions of the UNIX System use units other<br>
> than 512-byte blocks for st_blocks.<br>
> Using this value is nonportable"<br>
<br>
</span>That is correct. However, there is no portable method of determining<br>
the value used for st_blocks, so for our purposes here we may make the<br>
assumption that it is in fact 512 bytes.<br>
<br>
That means that the approach of calculating the correct value based on<br>
the environment variable as discussed in this thread does work (although<br>
you need to be careful to round up when needed).<br>
<br>
The NetBSD implementation of ls(1) takes the approach of setting the<br>
value for '-s' output to<br>
<br>
X = BLOCKSIZE/512<br>
Y = ( (st_blocks + (X - 1)) / X )<br>
<br>
st_blocks * 512 / BLOCKSIZE will get close, but occasionally be off by<br>
one.<br>
<span class="HOEnZb"><font color="#888888"><br>
-Jan<br>
</font></span><div class="HOEnZb"><div class="h5">_______________________________________________<br>
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