Q50383: Inference Rule May Fail When Spaces on Blank Command Line

Article: Q50383
Product(s): Microsoft Programming Utilities
Version(s): MS-DOS:1.01,1.1,1.11,1.12,1.13,1.2,1.3,1.4; OS/2:1.01,1.11,1.12,1.21
Operating System(s): 
Keyword(s): kb16bitonly
Last Modified: 30-OCT-1999

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The information in this article applies to:

- Microsoft NMAKE Utility for MS-DOS, versions 1.01, 1.1, 1.11, 1.12, 1.13, 1.2, 1.3, 1.4 
- Microsoft NMAKE Utility for OS/2, versions 1.01, 1.11, 1.12, 1.21 
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SUMMARY
=======

When using inference rules in an NMAKE description file, the target/dependency
line must be followed by a blank line (no space characters); otherwise, the
inference rule commands will not be executed. NMAKE checks this line for any
ASCII characters; if ANY characters exist, NMAKE will ignore the inference rule
and try to execute the line, even if it contains only a space or spaces.

The following is a simple example, which demonstrates this problem:

  .c.exe:
    cl $**
   
  ALL : main.exe
   
  main.exe : main.c
  <space>

Nothing happens if this description file is passed to NMAKE because the space
character causes NMAKE to assume there are explicit commands following the
target/dependency line, causing it to ignore the inference rule. Note that this
is expected behavior for NMAKE.

MORE INFORMATION
================

MAKE version 4.x inference rules/description blocks do not exhibit this
behavior. This is something to keep in mind when converting description files
from MAKE to NMAKE.

Additional query words: kbinf 1.10 1.20 1.30 1.40

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Keywords          : kb16bitonly 
Technology        : kbVCsearch kbAudDeveloper kbNMAKESearch kbNMAKE101DOS kbNMAKE110DOS kbNMAKE111DOS kbNMAKE112DOS kbNMAKE113DOS kbNMAKE120DOS kbNMAKE130DOS kbNMAKE140DOS kbNMAKE101OS2 kbNMAKE111OS2 kbNMAKE112OS2 kbNMAKE121OS2
Version           : MS-DOS:1.01,1.1,1.11,1.12,1.13,1.2,1.3,1.4; OS/2:1.01,1.11,1.12,1.21

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