processes plugin: Don't complain about a failed open(/proc/$PID/cmdline)

... if the error is ENOENT. This merely means we were too slow and that
we can safely ignore the process.

diff --git a/src/processes.c b/src/processes.c
index 670aa8d717dd19e1e745b1c15584ef2a90c8af3c..856296cc896ab6c4f66e5d67559ab2833b0efe86 100644 (file)
--- a/src/processes.c
+++ b/src/processes.c
@@ -903,13 +903,18 @@ static char *ps_get_cmdline (pid_t pid, char *name, char *buf, size_t buf_len)
        if ((pid < 1) || (NULL == buf) || (buf_len < 2))
                return NULL;
 
-       ssnprintf (file, sizeof (file), "/proc/%u/cmdline", pid);
+       ssnprintf (file, sizeof (file), "/proc/%u/cmdline",
+                       (unsigned int) pid);
 
+       errno = 0;
        fd = open (file, O_RDONLY);
        if (fd < 0) {
                char errbuf[4096];
-               WARNING ("processes plugin: Failed to open `%s': %s.", file,
-                               sstrerror (errno, errbuf, sizeof (errbuf)));
+               /* ENOENT means the process exited while we were handling it.
+                * Don't complain about this, it only fills the logs. */
+               if (errno != ENOENT)
+                       WARNING ("processes plugin: Failed to open `%s': %s.", file,
+                                       sstrerror (errno, errbuf, sizeof (errbuf)));
                return NULL;
        }
 
@@ -924,7 +929,7 @@ static char *ps_get_cmdline (pid_t pid, char *name, char *buf, size_t buf_len)
                status = read (fd, (void *)buf_ptr, len);
 
                if (status < 0) {
-                       char errbuf[4096];
+                       char errbuf[1024];
 
                        if ((EAGAIN == errno) || (EINTR == errno))
                                continue;