fix: compiler warnings in binary wrappers

Latest versions of compiler with high level of warnings enabled report
unused return value with setuid() and setgid() in binary wrappers. This
is now fixed with this commit, errno is reported in case of error.

Fix #70

Author: rezib

CHANGELOG.md

@@ -93,7 +93,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Static analysis errors reported by ruff tool with a simple initial
   configuration (#75).
 - Properly remove deprecated source RPM packages from repository after a
-  successful build (#58)
+  successful build (#58).
+- Compiler `-Wunused-result` warnings with binary wrappers (#70).
 - cli:
   - Avoid hazardous handling of unsupported errors, as a basis for better
     error management.

lib/wrappers/u-bin.c.in

@@ -35,8 +35,10 @@ int main(int argc, char **argv) {
 
     if (fork() == 0) {
         /* Become root before executing the command */
-        setuid(0);
-        setgid(0);
+        if(setuid(0))
+            perror("setuid");
+        if(setgid(0))
+            perror("setgid");
         if(execv(nargv[0], nargv))
             perror("execv");
         /* Exit code 255 if execve() fails */