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-rw-r--r--lib/bind/bsd/ftruncate.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/lib/bind/bsd/ftruncate.c b/lib/bind/bsd/ftruncate.c
new file mode 100644
index 0000000..b222c8b
--- /dev/null
+++ b/lib/bind/bsd/ftruncate.c
@@ -0,0 +1,64 @@
+#ifndef LINT
+static const char rcsid[] = "$Id: ftruncate.c,v 1.1.352.3 2005/06/22 22:05:45 marka Exp $";
+#endif
+
+/*! \file
+ * \brief
+ * ftruncate - set file size, BSD Style
+ *
+ * shortens or enlarges the file as neeeded
+ * uses some undocumented locking call. It is known to work on SCO unix,
+ * other vendors should try.
+ * The #error directive prevents unsupported OSes
+ */
+
+#include "port_before.h"
+
+#if defined(M_UNIX)
+#define OWN_FTRUNCATE
+#include <stdio.h>
+#ifdef _XOPEN_SOURCE
+#undef _XOPEN_SOURCE
+#endif
+#ifdef _POSIX_SOURCE
+#undef _POSIX_SOURCE
+#endif
+
+#include <fcntl.h>
+
+#include "port_after.h"
+
+int
+__ftruncate(int fd, long wantsize) {
+ long cursize;
+
+ /* determine current file size */
+ if ((cursize = lseek(fd, 0L, 2)) == -1)
+ return (-1);
+
+ /* maybe lengthen... */
+ if (cursize < wantsize) {
+ if (lseek(fd, wantsize - 1, 0) == -1 ||
+ write(fd, "", 1) == -1) {
+ return (-1);
+ }
+ return (0);
+ }
+
+ /* maybe shorten... */
+ if (wantsize < cursize) {
+ struct flock fl;
+
+ fl.l_whence = 0;
+ fl.l_len = 0;
+ fl.l_start = wantsize;
+ fl.l_type = F_WRLCK;
+ return (fcntl(fd, F_FREESP, &fl));
+ }
+ return (0);
+}
+#endif
+
+#ifndef OWN_FTRUNCATE
+int __bindcompat_ftruncate;
+#endif
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