diff --git a/src/fop.rs b/src/fop.rs
index 9f547b1..66b7e82 100644
--- a/src/fop.rs
+++ b/src/fop.rs
@@ -30,11 +30,23 @@ use getopt::GetOpt;
 use strerror::StrError;
 use sysexits::{ EX_DATAERR, EX_IOERR, EX_UNAVAILABLE, EX_USAGE };
 
+#[cfg(target_os="openbsd")] use sysexits::EX_OSERR;
+#[cfg(target_os="openbsd")] extern crate openbsd;
+#[cfg(target_os="openbsd")] use openbsd::{ Promises, pledge };
+
 fn main() {
 	let argv = args().collect::<Vec<String>>();
 	let mut d = '\u{1E}'.to_string(); /* ASCII record separator */
 	let mut optind = 1;
 
+	if cfg!(target_os="openbsd") {
+		let promises = Promises::new("stdio proc exec");
+		if let Err(e) = pledge(Some(promises), None) {
+			eprintln!("{}: {}", argv[0], e.strerror());
+			exit(EX_OSERR);
+		}
+	}
+
 	let usage = format!(
 		"Usage: {} [-d delimiter] index command [args...]",
 		argv[0],