files, replacing configuration parameters in them with appropriate
values. The files that @code{configure} creates are:
-@itemize @bullet
+@itemize @minus
@item
one or more @file{Makefile} files, one in each subdirectory of the
package (@pxref{Makefile Substitutions});
To be compatible with Ash 0.2:
-@itemize @bullet
+@itemize @minus
@item
don't use @samp{$?} after expanding empty or unset variables:
@node File System Conventions, Shell Substitutions, File Descriptors, Portable Shell
@subsection File System Conventions
-While @command{autoconf} and friends will usually be run on some Unix variety,
-it can and will be used on other systems, most notably @sc{dos} variants.
-This impacts several assumptions regarding file- and pathnames.
+While @command{autoconf} and friends will usually be run on some Unix
+variety, it can and will be used on other systems, most notably @sc{dos}
+variants. This impacts several assumptions regarding file- and
+pathnames.
@noindent
For example, the following code:
@example
-case "$foo_dir" in
+case $foo_dir in
/*) # Absolute
;;
*)
separator. The canonical way to check for absolute paths is:
@example
-case "$foo_dir" in
- [\\/]* | ?:[\\/]) # Absolute
+case $foo_dir in
+ [\\/]* | ?:[\\/]* ) # Absolute
;;
*)
foo_dir=$dots$foo_dir ;;
variable). @command{autoconf} sets this to the appropriate value (@samp{:}
or @samp{;}) when it starts up.
-File names need extra care as well. While @sc{dos}-based environments that are
-Unixy enough to run @command{autoconf} (such as @sc{djgpp}) will usually be able
-to handle long file names properly, there are still limitations that can
-seriously break packages:
+File names need extra care as well. While @sc{dos}-based environments
+that are Unixy enough to run @command{autoconf} (such as DJGPP) will
+usually be able to handle long file names properly, there are still
+limitations that can seriously break packages:
-@itemize @minus
+@table @asis
@item No multiple dots
-@sc{dos} cannot handle multiple dots in filenames. This is an especially important
-thing to remember when building a portable configure script, as
-@command{autoconf} uses a .in suffix for template files.
+@sc{dos} cannot handle multiple dots in filenames. This is an
+especially important thing to remember when building a portable
+configure script, as @command{autoconf} uses a .in suffix for template
+files.
This is perfectly OK on Unices:
@end example
@item Case insensitivity
-@sc{dos} is case insensitive, so you cannot, for example, have both a file called
-@samp{INSTALL} and a directory called @samp{install}. This also affects
-@command{make}; if there's a file called @samp{INSTALL} in the directory,
-@command{make install} will do nothing (unless the @samp{install} target is
-marked as PHONY).
+@sc{dos} is case insensitive, so you cannot, for example, have both a
+file called @samp{INSTALL} and a directory called @samp{install}. This
+also affects @command{make}; if there's a file called @samp{INSTALL} in
+the directory, @command{make install} will do nothing (unless the
+@samp{install} target is marked as PHONY).
@item The 8+3 limit
-Because the @sc{dos} file system only stores the first 8 characters of the filename
-and the first 3 of the extension, those must be unique. That means that
-@samp{foobar-part1.c}, @samp{foobar-part2.c} and @samp{foobar-prettybird.c}
-all resolve to the same filename (@samp{FOOBAR-P.C}). The same goes for
-@samp{foo.bar} and @samp{foo.bartender}.
-@end itemize
+Because the @sc{dos} file system only stores the first 8 characters of
+the filename and the first 3 of the extension, those must be unique.
+That means that @samp{foobar-part1.c}, @samp{foobar-part2.c} and
+@samp{foobar-prettybird.c} all resolve to the same filename
+(@samp{FOOBAR-P.C}). The same goes for @samp{foo.bar} and
+@samp{foo.bartender}.
+@end table
@node Shell Substitutions, Assignments, File System Conventions, Portable Shell
@subsection Shell Substitutions
@item PATH_SEPARATOR
@evindex PATH_SEPARATOR
-On @sc{djgpp} systems, the @code{PATH_SEPARATOR} variable can be set to either
-@samp{:} or @samp{;} to control the path separator @command{bash} uses
-to set up certain environment variables (such as @code{PATH}). Since this
-only works inside bash, you want autoconf to detect the regular @sc{dos} path
-separator @samp{;}, so it can be safely substituted in files that may
-not support @samp{;} as path separator. So either unset this variable
-or set it to @samp{;}.
+On DJGPP systems, the @code{PATH_SEPARATOR} variable can be set to
+either @samp{:} or @samp{;} to control the path separator @command{bash}
+uses to set up certain environment variables (such as
+@code{PATH}). Since this only works inside bash, you want autoconf to
+detect the regular @sc{dos} path separator @samp{;}, so it can be safely
+substituted in files that may not support @samp{;} as path separator. So
+either unset this variable or set it to @samp{;}.
@item RANDOM
@evindex RANDOM
@c -----------------
@cindex @command{exit}
The default value of @command{exit} is supposed to be @code{$?},
-unfortunately some shells, such as the @sc{djgpp} port of Bash 2.04, just
+unfortunately some shells, such as the DJGPP port of Bash 2.04, just
perform @samp{exit 0}.
@example
Don't rely on @command{ln} having a @option{-f} option. Symbolic links
are not available on old systems, use @samp{ln} as a fall back.
-For versions of the @sc{djgpp} before 2.04, @command{ln} emulates soft
-links for executables by generating a stub that in turn calls the real
+For versions of the DJGPP before 2.04, @command{ln} emulates soft links
+for executables by generating a stub that in turn calls the real
program. This feature also works with nonexistent files like in the
Unix spec. So @samp{ln -s file link} will generate @file{link.exe},
which will attempt to call @file{file.exe} if run. But this feature only
works for executables, so @samp{cp -p} is used instead for these
-systems. @sc{djgpp} version 2.04 and later have full symlink support.
+systems. DJGPP version 2.04 and later have full symlink support.
@item @command{mv}
projects / thirdparty / autoconf.git / commitdiff
