Follow Techotopia on Twitter

On-line Guides
All Guides
eBook Store
iOS / Android
Linux for Beginners
Office Productivity
Linux Installation
Linux Security
Linux Utilities
Linux Virtualization
Linux Kernel
System/Network Admin
Programming
Scripting Languages
Development Tools
Web Development
GUI Toolkits/Desktop
Databases
Mail Systems
openSolaris
Eclipse Documentation
Techotopia.com
Virtuatopia.com

How To Guides
Virtualization
General System Admin
Linux Security
Linux Filesystems
Web Servers
Graphics & Desktop
PC Hardware
Windows
Problem Solutions
Privacy Policy

  




 

 

[ < ] [ > ]   [ << ] [ Up ] [ >> ]         [Top] [Contents] [Index] [ ? ]

7.3 Conditionals that Test Flags

You can write a conditional that tests make command flags such as `-t' by using the variable MAKEFLAGS together with the findstring function (see section Functions for String Substitution and Analysis). This is useful when touch is not enough to make a file appear up to date.

The findstring function determines whether one string appears as a substring of another. If you want to test for the `-t' flag, use `t' as the first string and the value of MAKEFLAGS as the other.

For example, here is how to arrange to use `ranlib -t' to finish marking an archive file up to date:

 
archive.a: ...
ifneq (,$(findstring t,$(MAKEFLAGS)))
        +touch archive.a
        +ranlib -t archive.a
else
        ranlib archive.a
endif

The `+' prefix marks those command lines as "recursive" so that they will be executed despite use of the `-t' flag. See section Recursive Use of make.



 
 
  Published under the terms of the GNU General Public License Design by Interspire