lorder - Finds the best order for member files in an object library
The lorder command is essentially obsolete. Use the following command in its place: % ar -ts file.a
The lorder command reads one or more object or library archive files, looks for external references, and writes a list of paired filenames to standard output. The first of each pair of files contains references to identifiers that are defined in the second file. You can send this list to the tsort command to find an ordering of a library member file suitable for 1-pass access by ld.
If object files do not end with
overlooks them and attributes their global symbols and references
to some other file.
To create a subroutine library, enter:
lorder charin.o scanfld.o scan.o scanln.o |
tsort | xargs ar qv libsubs.a
(Enter this command entirely on one line, not on two lines as shown above.)
This creates a subroutine library named libsubs.a that contains charin.o, scanfld.o, scan.o, and scanln.o. The ordering of the object modules in the library is important. The lorder and tsort commands together add the subroutines to the library in the proper order.
Suppose that scan.o calls entry points in scanfld.o and scanln.o. scanfld.o also calls entry points in charin.o. First, the lorder command creates a list of pairs that shows these dependencies: charin.o charin.o scanfld.o scanfld.o scan.o scan.o scanln.o scanln.o scanfld.o charin.o scanln.o charin.o scan.o scanfld.o
This list is piped to the tsort command, which converts the list into the ordering that is needed:
scan.o scanfld.o scanln.o charin.o
Note that each module precedes the module it calls. charin.o, which does not call another module, is last. The second list is then piped to xargs, which constructs and runs the following ar command: ar qv libsubs.a scan.o scanfld.o scanln.o charin.o
command creates the properly ordered library.
Commands: ar(1), as(1), cc(1), ld(1), make(1), nm(1), size(1), strip(1), tsort(1), xargs(1)
Files: a.out(4), ar(4)