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Diffstat (limited to 'ruby_1_8_6/missing/dup2.c')
-rw-r--r--ruby_1_8_6/missing/dup2.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/ruby_1_8_6/missing/dup2.c b/ruby_1_8_6/missing/dup2.c
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index 0000000000..e7cc46f4c1
--- /dev/null
+++ b/ruby_1_8_6/missing/dup2.c
@@ -0,0 +1,61 @@
+/*
+ * Public domain dup2() lookalike
+ * by Curtis Jackson @ AT&T Technologies, Burlington, NC
+ * electronic address: burl!rcj
+ *
+ * dup2 performs the following functions:
+ *
+ * Check to make sure that fd1 is a valid open file descriptor.
+ * Check to see if fd2 is already open; if so, close it.
+ * Duplicate fd1 onto fd2; checking to make sure fd2 is a valid fd.
+ * Return fd2 if all went well; return BADEXIT otherwise.
+ */
+
+#include "config.h"
+
+#if defined(HAVE_FCNTL)
+# include <fcntl.h>
+#endif
+
+#if !defined(HAVE_FCNTL) || !defined(F_DUPFD)
+# include <errno.h>
+#endif
+
+#define BADEXIT -1
+
+int
+dup2(fd1, fd2)
+int fd1, fd2;
+{
+#if defined(HAVE_FCNTL) && defined(F_DUPFD)
+ if (fd1 != fd2) {
+#ifdef F_GETFL
+ if (fcntl(fd1, F_GETFL) < 0)
+ return BADEXIT;
+ if (fcntl(fd2, F_GETFL) >= 0)
+ close(fd2);
+#else
+ close(fd2);
+#endif
+ if (fcntl(fd1, F_DUPFD, fd2) < 0)
+ return BADEXIT;
+ }
+ return fd2;
+#else
+ extern int errno;
+ int i, fd, fds[256];
+
+ if (fd1 == fd2) return 0;
+ close(fd2);
+ for (i=0; i<256; i++) {
+ fd = fds[i] = dup(fd1);
+ if (fd == fd2) break;
+ }
+ while (i) {
+ close(fds[i--]);
+ }
+ if (fd == fd2) return 0;
+ errno = EMFILE;
+ return BADEXIT;
+#endif
+}