%general-entities; ]> Multiarch Wrapper Create the source file: cat > multiarch_wrapper.c << "EOF" #include <stdio.h> #include <stdlib.h> #include <string.h> #include <errno.h> #ifndef DEFAULT_ARCH # define DEFAULT_ARCH "64" #endif int main (int argc, char *argv[]) { char *use_arch; if ((use_arch = getenv("USE_ARCH")) == NULL) use_arch = DEFAULT_ARCH; char *filename = malloc(strlen(argv[0]) + strlen(use_arch) + 2); strcpy(filename, argv[0]); strcat(filename, "-"); strcat(filename, use_arch); int ret = execvp(filename, argv); if ((ret != 0)&&(errno != 0)) { char *errmsg = malloc(strlen(filename) + 19); strcpy(errmsg, "Unable to execute "); strcat(errmsg, filename); perror(errmsg); free(errmsg); } free(filename); return ret; } EOF Compile and Install the Multiarch Wrapper: gcc ${BUILD64} multiarch_wrapper.c -o /usr/bin/multiarch_wrapper This multiarch wrapper is going to be used later on in the book with perl. It will also be very useful outside of the base CLFS system. Creating the testcase: echo 'echo "32bit Version"' > test-32 echo 'echo "64bit Version"' > test-64 chmod 755 test-32 test-64 ln -sv /usr/bin/multiarch_wrapper test Testing the wrapper: USE_ARCH=32 ./test USE_ARCH=64 ./test The output of the above command should be: 32bit Version 64bit Version Installed programs multiarch_wrapper Short Descriptions multiarch_wrapper Will execute a different program based on the USE_ARCH variable. The USE_ARCH variable will be the suffix of the executed program. multiarch_wrapper