Add user page and patch pages for tlecarrour.

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+[[!meta copyright="Copyright © 2010 Free Software Foundation, Inc."]]
+
+[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
+id="license" text="Permission is granted to copy, distribute and/or modify this
+document under the terms of the GNU Free Documentation License, Version 1.2 or
+any later version published by the Free Software Foundation; with no Invariant
+Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
+is included in the section entitled [[GNU Free Documentation
+License|/fdl]]."]]"""]]
+
+
+memstat
+=======
+
+Lists all the processes, executables, and shared libraries that are using up virtual memory. It's helpful to see how the shared memory is used and which 'old' libs are loaded.  
+**Home page**: [[http://sourceforge.net/projects/memstattool]]
+
+[[!toc startlevel=2]]
+
+
+* * *
+
+
+Log
+---
+
+* **Started**: 2012-01-20
+* **Discussed**: [2012-01-21](http://lists.debian.org/debian-hurd/2012/01/msg00081.html)
+* **Draft Submitted**: [2012-01-25](http://lists.debian.org/debian-hurd/2012/01/msg00122.html)
+* **Submitted**: -
+* **Accepted**: -
+
+
+* * *
+
+
+ToDo
+----
+
+Here is the output of `grep -R PATH_MAX memstat-0.9/*`:
+
+    memstat.c:    char *p, major[8], minor[8], buff[PATH_MAX + 300], *path, perm[4];
+    memstat.c:    char linkname[PATH_MAX], filename[PATH_MAX];
+    memstat.c:    if ((len = readlink(filename, linkname, PATH_MAX)) == -1) {
+
+
+* * *
+
+
+Comments
+--------
+
+Here are comments on the patch...
+
+    +#define FMT_PROC_MAPS "/proc/%d/maps"
+    +#define FMT_PROC_EXE  "/proc/%d/exe"
+
+Define string formats.
+
+     static void read_proc(void)
+     {
+         unsigned int nread, pid;
+         unsigned long inode, lo, hi, offs;
+    -    char *p, major[8], minor[8], buff[PATH_MAX + 300], *path, perm[4];
+    +    char *p, major[8], minor[8], *path, perm[4];
+    +    char *buff = NULL;
+    +    size_t buff_size = 0;
+
+In this function we turn `buff` into dynamically allocated string.
+
+
+    -   sprintf(buff, "/proc/%d/maps", pid);
+    -   f = fopen(buff, "r");
+    +   char filename[sizeof(FMT_PROC_MAPS) + (sizeof(int) * 3) + 1];
+    +   sprintf(filename, FMT_PROC_MAPS, pid);
+    +   f = fopen(filename, "r");
+
+Compute the maximum size of `filename` using `sizeof(int) * 3` as explainend in the [[porting guide|porting_guide_for_dummies]].
+
+
+    -   while (fgets(buff, sizeof(buff), f)) {
+    +   while (!feof(f)) {
+    +       buff = get_line(f);
+    +       if (buff == NULL)
+    +       break;
+
+Read a line from the file using [[get_line()|porting_guide_for_dummies]].
+
+
+    -       if ((strlen(buff) == 10) && (strcmp(buff, " (deleted)") == 0))
+    +       if ((strlen(buff) == 10) && (strcmp(buff, " (deleted)") == 0)) {
+    +       free(buff);
+            continue;
+    +       }
+            nread = sscanf(buff, "%lx %lx %4s %lx %s %s %lu %as", &lo, &hi, perm, &offs, major, minor, &inode, &path);
+    +       free(buff);
+
+Free the `buff` when it's not used anymore.
+
+
+    +       buff_size = 4; /* size of the format string without "%x" expressions */
+    +       buff_size += strlen(major);
+    +       buff_size += strlen(minor);
+    +       buff_size += sizeof(int) * 3 + 1; /* inode */
+    +       buff_size += 1; /* '\0' */
+    +       buff = malloc(buff_size);
+    +       if (buff == NULL) {
+    +           perror("Cannot allocate memory!");
+    +           exit(1);
+    +       }
+
+Compute the size that the `buff` must have.
+
+
+    -   char linkname[PATH_MAX], filename[PATH_MAX];
+    -   ssize_t len;
+    +   char *linkname = NULL;
+    +   struct stat sb;
+    +   ssize_t len = -1;
+
+In this function we turn linkname into dynamically allocated string. 
+filename will be declared later.
+
+
+    -   sprintf(filename, "/proc/%d/exe", pid);
+    -   if ((len = readlink(filename, linkname, PATH_MAX)) == -1) {
+    +   char filename[sizeof(FMT_PROC_EXE) + (sizeof(int) * 3) + 1];
+    +   sprintf(filename, FMT_PROC_EXE, pid);
+
+Same as above with `FMT_PROC_MAPS`.
+
+
+    +   if (lstat(filename, &sb) == -1) {
+    +       perror("lstat");
+    +       deleted = 1;
+    +   }
+    +   else {
+    +       linkname = malloc(sb.st_size + 1);
+    +       if (linkname == NULL) {
+    +       fprintf(stderr, "insufficient memory\n");
+    +       deleted = 1;
+    +       }
+    +       else {
+    +       len = readlink(filename, linkname, sb.st_size + 1);
+    +       }
+    +   }
+    +   if (len < 0 || len > sb.st_size) {
+            fprintf(stderr, "Cannot read link information for %s\n", filename);
+            deleted = 1;
+        }
+    -   linkname[len] = '\0';
+    +   else {
+    +       linkname[sb.st_size] = '\0';
+    +   }
+
+Use `readlink()` as explained in the porting guide. 
+Require lstat to get the link size.
+
+
+    +   free(linkname);
+Free dynamically allocated variable that is not used anymore.
+