codeblocks-ep/help/html/programmerHelp/make/Interrupts.html at master · maifeeulasad/codeblocks-ep · GitHub

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Node:<a name="Interrupts">Interrupts</a>,
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<h3 class="section">Interrupting or Killing <code>make</code></h3>

   <p>If <code>make</code> gets a fatal signal while a command is executing, it may
delete the target file that the command was supposed to update.  This is
done if the target file's last-modification time has changed since
<code>make</code> first checked it.

   <p>The purpose of deleting the target is to make sure that it is remade from
scratch when <code>make</code> is next run.  Why is this?  Suppose you type
<kbd>Ctrl-c</kbd> while a compiler is running, and it has begun to write an
object file <code>foo.o</code>.  The <kbd>Ctrl-c</kbd> kills the compiler, resulting
in an incomplete file whose last-modification time is newer than the source
file <code>foo.c</code>.  But <code>make</code> also receives the <kbd>Ctrl-c</kbd> signal
and deletes this incomplete file.  If <code>make</code> did not do this, the next
invocation of <code>make</code> would think that <code>foo.o</code> did not require
updating--resulting in a strange error message from the linker when it
tries to link an object file half of which is missing.

   <p>You can prevent the deletion of a target file in this way by making the
special target <code>.PRECIOUS</code> depend on it.  Before remaking a target,
<code>make</code> checks to see whether it appears on the prerequisites of
<code>.PRECIOUS</code>, and thereby decides whether the target should be deleted
if a signal happens.  Some reasons why you might do this are that the
target is updated in some atomic fashion, or exists only to record a
modification-time (its contents do not matter), or must exist at all
times to prevent other sorts of trouble.

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