Hi,<div><br></div><div>In Linux code we add a guard macro to avoid multiple declarations of identifiers. </div><div>But I see some macros defined with trailing underscores.</div><div>e.g. In arch/x86/include/asm/ </div><div>
<br></div><div>Normally it is defined like,</div><div> </div><div> #ifndef _ASM_X86_ALTERNATIVE_H</div><div> #define _ASM_X86_ALTERNATIVE_H</div><div><div><br></div><div>But in some files I see trailing underscore after H ,</div>
<div><br></div><div>e.g. arch/x86/include/asm/intel_scu_ipc.h</div><div><br></div><div><div><br></div><div>#ifndef _ASM_X86_INTEL_SCU_IPC_H_</div><div>#define  _ASM_X86_INTEL_SCU_IPC_H_</div></div><div><br></div><div>There are others files also </div>
<div>arch/x86/include/asm/irqflags.h</div><div><a href="http://lxr.linux.no/#linux+v3.3.2/arch/x86/include/asm/probe_roms.h">http://lxr.linux.no/#linux+v3.3.2/arch/x86/include/asm/probe_roms.h</a></div><div><br></div><div>
<br></div><div>DOES THIS TRAILING UNDERSCORE HAS SPECIAL MEANING ???</div><div><br></div><div>Thanks</div>-- <br><br>Pritam Bankar<br>
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