[bug#70494] [PATCH 13/23] syscalls: Add unshare.

[Christopher Baines]

* guix/build/syscalls.scm (unshare): New procedure.

Change-Id: I7caad207117b17b349290e680277f650c51d2f3b
---
 guix/build/syscalls.scm | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/guix/build/syscalls.scm b/guix/build/syscalls.scm
index 487ee68b43..492a229938 100644
--- a/guix/build/syscalls.scm
+++ b/guix/build/syscalls.scm
@@ -36,6 +36,7 @@ (define-module (guix build syscalls)
   #:use-module (srfi srfi-11)
   #:use-module (srfi srfi-19)
   #:use-module (srfi srfi-26)
+  #:use-module (srfi srfi-71)
   #:use-module (ice-9 rdelim)
   #:use-module (ice-9 regex)
   #:use-module (ice-9 match)
@@ -121,6 +122,7 @@ (define-module (guix build syscalls)
             mkdtemp!
             fdatasync
             pivot-root
+            unshare
             scandir*
             getxattr
             setxattr
@@ -1183,6 +1185,16 @@ (define pivot-root
                  (list new-root put-old (strerror err))
                  (list err)))))))
 
+(define unshare
+  (false-if-exception
+   (let ((proc (syscall->procedure int "unshare" (list int))))
+     (lambda (flags)
+       (let ((ret err (proc flags)))
+         (unless (zero? ret)
+           (throw 'system-error "unshare" "~d ~d: ~A"
+                  (list flags (strerror err))
+                  (list err))))))))
+
 
 ;;;
 ;;; Opendir & co.
-- 
2.41.0