14.2 Utilities in Makefiles

Write the Makefile commands (and any shell scripts, such as configure) to run in sh, not in csh. Don't use any special features of ksh or bash.

The configure script and the Makefile rules for building and installation should not use any utilities directly except these:

cat cmp cp diff echo egrep expr false grep install-info ln ls mkdir mv pwd rm rmdir sed sleep sort tar test touch true

The compression program gzip can be used in the dist rule.

Stick to the generally supported options for these programs. For example, don't use `mkdir -p', convenient as it may be, because most systems don't support it.

It is a good idea to avoid creating symbolic links in makefiles, since a few systems don't support them.

The Makefile rules for building and installation can also use compilers and related programs, but should do so via make variables so that the user can substitute alternatives. Here are some of the programs we mean:

ar bison cc flex install ld ldconfig lex make makeinfo ranlib texi2dvi yacc

Use the following make variables to run those programs:

$(AR) $(BISON) $(CC) $(FLEX) $(INSTALL) $(LD) $(LDCONFIG) $(LEX) $(MAKE) $(MAKEINFO) $(RANLIB) $(TEXI2DVI) $(YACC)

When you use ranlib or ldconfig, you should make sure nothing bad happens if the system does not have the program in question. Arrange to ignore an error from that command, and print a message before the command to tell the user that failure of this command does not mean a problem. (The Autoconf `AC_PROG_RANLIB' macro can help with this.)

If you use symbolic links, you should implement a fallback for systems that don't have symbolic links.

Additional utilities that can be used via Make variables are:

chgrp chmod chown mknod

It is ok to use other utilities in Makefile portions (or scripts) intended only for particular systems where you know those utilities exist.