alan@ajf-rh ~$ g++ -laugeas aug.cpp
/tmp/ccKAoo7L.o: In function `main':
aug.cpp:(.text+0x1f): undefined reference to `aug_init(char const*, char const*, unsigned int)'
aug.cpp:(.text+0x39): undefined reference to `aug_set(augeas*, char const*, char const*)'
aug.cpp:(.text+0x45): undefined reference to `aug_close(augeas*)'
collect2: ld returned 1 exit status
alan@ajf-rh ~$ grep aug_init /usr/include/augeas.h
/* Function: aug_init
augeas *aug_init(const char *root, const char *loadpath, unsigned int flags);
alan@ajf-rh ~$ objdump -t /usr/lib64/libaugeas.so.0.13.1 |grep aug_init
00000000000061e0 g     F .text	000000000000067f              aug_init
alan@ajf-rh ~$ ll /usr/lib64/libaugeas.*
-rw-r--r-- 1 root root 1530886 May 23 19:14 /usr/lib64/libaugeas.a
-rwxr-xr-x 1 root root     957 May 23 19:14 /usr/lib64/libaugeas.la
lrwxrwxrwx 1 root root      19 May 23 19:14 /usr/lib64/libaugeas.so -> libaugeas.so.0.13.1
lrwxrwxrwx 1 root root      19 May 23 19:14 /usr/lib64/libaugeas.so.0 -> libaugeas.so.0.13.1
-rwxr-xr-x 1 root root  915492 May 23 19:14 /usr/lib64/libaugeas.so.0.13.1
alan@ajf-rh ~$ pkg-config --cflags --libs augeas
 -laugeas

alan@ajf-rh ~$ cat aug.cpp
#include <augeas.h>

int main(int argc, char *argv[])
{
        augeas *aug = aug_init("/", "/usr/share/augeas/lenses/", 0);
        aug_set(aug, "/files/etc/ssh/sshd_config/PermitRootLogin", "no");
        aug_close(aug);
	return 0;
}