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--- proc:maps_file [2017/04/05 09:54] – created peter
+++ proc:maps_file [2020/07/15 09:30] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
 ====== Proc - maps file ======
+The **/proc/PID/maps** file containing the currently mapped memory regions and their access permissions.
+The format is:
+^address^perms^offset^dev^inode^pathname^
+|08048000-08049000|r-xp|00000000|03:00|8312|/opt/test|
+|08049000-0804a000|rw-p|00001000|03:00|8312|/opt/test|
+|0804a000-0806b000|rw-p|00000000|00:00|0|[heap]|
+|a7cb1000-a7cb2000|<nowiki>---p</nowiki>|00000000|00:00|0| |
+|a7cb2000-a7eb2000|rw-p|00000000|00:00|0| |
+|a7eb2000-a7eb3000|<nowiki>---p</nowiki>|00000000|00:00|0| |
+|a7eb3000-a7ed5000|rw-p|00000000|00:00|0| |
+|a7ed5000-a8008000|r-xp|00000000|03:00|4222|/lib/libc.so.6|
+|a8008000-a800a000|<nowiki>r--p</nowiki>|00133000|03:00|4222|/lib/libc.so.6|
+|a800a000-a800b000|rw-p|00135000|03:00|4222|/lib/libc.so.6|
+|a800b000-a800e000|rw-p|00000000|00:00|0| |
+|a800e000-a8022000|r-xp|00000000|03:00|14462|/lib/libpthread.so.0|
+|a8022000-a8023000|<nowiki>r--p</nowiki>|00013000|03:00|14462|/lib/libpthread.so.0|
+|a8023000-a8024000|rw-p|00014000|03:00|14462|/lib/libpthread.so.0|
+|a8024000-a8027000|rw-p|00000000|00:00|0| |
+|a8027000-a8043000|r-xp|00000000|03:00|8317|/lib/ld-linux.so.2|
+|a8043000-a8044000|<nowiki>r--p</nowiki>|0001b000|03:00|8317|/lib/ld-linux.so.2|
+|a8044000-a8045000|rw-p|0001c000|03:00|8317|/lib/ld-linux.so.2|
+|aff35000-aff4a000|rw-p|00000000|00:00|0|[stack]|
+|ffffe000-fffff000|r-xp|00000000|00:00|0|[vdso]|
+where:
+  * **address** is the address space in the process that it occupies.
+  * **perms** is a set of permissions:
+    * r = read.
+    * w = write.
+    * x = execute.
+    * s = shared.
+    * p = private (copy on write).
+  * **offset** is the offset into the mapping.
+  * **dev** is the device (major:minor).
+  * **inode** is the inode  on that device.
+    * 0 indicates that  no inode is associated with the memory region, as the case would be with BSS (uninitialized data).
+  * **pathname** shows the name associated file for this mapping.  If the mapping is not associated with a file:
+    * [heap]   = the heap of the program.
+    * [stack]  = the stack of the main process.
+    * [vdso]   = the "virtual dynamic shared object", the kernel system call handler.
+    * If empty, the mapping is anonymous.