add rudimentary prctl syscall wrapper

2 files changed, 6 insertions, 4 deletions

diff --git a/examples/withallsubuids.py b/examples/withallsubuids.py
index 8b90e9a..ead0482 100755
--- a/examples/withallsubuids.py
+++ b/examples/withallsubuids.py
@@ -47,13 +47,10 @@ def main() -> None:
     while caps:
         cap = caps & (~caps + 1)
         caps ^= cap
-        linuxnamespaces.call_libc(
-            "prctl",
+        linuxnamespaces.prctl(
             47,  # PR_CAP_AMBIENT
             2,  # PR_CAP_AMBIENT_RAISE
             cap.bit_length() - 1,
-            0,
-            0,
         )
     if len(sys.argv) > 1:
         os.execvp(sys.argv[1], sys.argv[1:])
diff --git a/linuxnamespaces/syscalls.py b/linuxnamespaces/syscalls.py
index c98d776..ab715f2 100644
--- a/linuxnamespaces/syscalls.py
+++ b/linuxnamespaces/syscalls.py
@@ -622,6 +622,11 @@ def pivot_root(new_root: PathConvertible, put_old: PathConvertible) -> None:
     """Python wrapper for pivot_root(2)."""
     call_libc("pivot_root", os.fsencode(new_root), os.fsencode(put_old))
 
+def prctl(
+    option: int, arg2: int = 0, arg3: int = 0, arg4: int = 0, arg5: int = 0
+) -> int:
+    """Python wrapper for prctl(2)."""
+    return call_libc("prctl", option, arg2, arg3, arg4, arg5)
 
 def setns(fd: int, nstype: CloneFlags = CloneFlags.NONE) -> None:
     """Python wrapper for setns(2)."""