[PATCH 1/1] mmap.2: improve example

[Rahul Bedarkar <rahulbedarkar89@xxxxxxxxx>]

free resources on error paths and at the end after use.

Signed-off-by: Rahul Bedarkar <rahulbedarkar89@xxxxxxxxx>
---
 man2/mmap.2 | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/man2/mmap.2 b/man2/mmap.2
index 0f2f277..cede984 100644
--- a/man2/mmap.2
+++ b/man2/mmap.2
@@ -765,8 +765,10 @@ main(int argc, char *argv[])
     if (fd == \-1)
         handle_error("open");
 
-    if (fstat(fd, &sb) == \-1)           /* To obtain file size */
+    if (fstat(fd, &sb) == \-1) {          /* To obtain file size */
+        close(fd);
         handle_error("fstat");
+    }
 
     offset = atoi(argv[2]);
     pa_offset = offset & ~(sysconf(_SC_PAGE_SIZE) \- 1);
@@ -774,6 +776,7 @@ main(int argc, char *argv[])
 
     if (offset >= sb.st_size) {
         fprintf(stderr, "offset is past end of file\\n");
+        close(fd);
         exit(EXIT_FAILURE);
     }
 
@@ -789,18 +792,27 @@ main(int argc, char *argv[])
 
     addr = mmap(NULL, length + offset \- pa_offset, PROT_READ,
                 MAP_PRIVATE, fd, pa_offset);
-    if (addr == MAP_FAILED)
+    if (addr == MAP_FAILED) {
+        close(fd);
         handle_error("mmap");
+    }
 
     s = write(STDOUT_FILENO, addr + offset \- pa_offset, length);
     if (s != length) {
-        if (s == \-1)
+        if (s == \-1) {
+            munmap(addr, length + offset \- pa_offset);
+            close(fd);
             handle_error("write");
+        }
 
+        munmap(addr, length + offset \- pa_offset);
+        close(fd);
         fprintf(stderr, "partial write");
         exit(EXIT_FAILURE);
     }
 
+    munmap(addr, length + offset \- pa_offset);
+    close(fd);
     exit(EXIT_SUCCESS);
 }
 .fi
-- 
1.8.3.2

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