free: more compatible output. +16 bytes. Closes bug 2383.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 20 insertions, 8 deletions

diff --git a/procps/free.c b/procps/free.c
index 473d70be8..db70712cf 100644
--- a/procps/free.c
+++ b/procps/free.c
@@ -53,29 +53,41 @@ int free_main(int argc UNUSED_PARAM, char **argv IF_NOT_DESKTOP(UNUSED_PARAM))
                 info.bufferram *= mem_unit;
         }
 
-        printf("      %13s%13s%13s%13s%13s\n",
+        printf("     %13s%13s%13s%13s%13s\n",
                 "total",
                 "used",
                 "free",
                 "shared", "buffers" /* swap and total don't have these columns */
+                /* procps version 3.2.8 also shows "cached" column, but
+                 * sysinfo() does not provide this value, need to parse
+                 * /proc/meminfo instead and get "Cached: NNN kB" from there.
+                 */
         );
-        printf("%6s%13lu%13lu%13lu%13lu%13lu\n", "Mem:",
+#define FIELDS_5 "%13lu%13lu%13lu%13lu%13lu\n"
+#define FIELDS_3 (FIELDS_5 + 2*5)
+#define FIELDS_2 (FIELDS_5 + 3*5)
+        printf("Mem: ");
+        printf(FIELDS_5,
                 info.totalram,
                 info.totalram - info.freeram,
                 info.freeram,
                 info.sharedram, info.bufferram
         );
+        /* Show alternate, more meaningful busy/free numbers by counting
+         * buffer cache as free memory (make it "-/+ buffers/cache"
+         * if/when we add support for "cached" column): */
+        printf("-/+ buffers:      ");
+        printf(FIELDS_2,
+                info.totalram - info.freeram - info.bufferram,
+                info.freeram + info.bufferram
+        );
 #if BB_MMU
-        printf("%6s%13lu%13lu%13lu\n", "Swap:",
+        printf("Swap:");
+        printf(FIELDS_3,
                 info.totalswap,
                 info.totalswap - info.freeswap,
                 info.freeswap
         );
-        printf("%6s%13lu%13lu%13lu\n", "Total:",
-                info.totalram + info.totalswap,
-                (info.totalram - info.freeram) + (info.totalswap - info.freeswap),
-                info.freeram + info.freeswap
-        );
 #endif
         return EXIT_SUCCESS;
 }