Is there any system function/api to get values like /proc/<pid>/status ???

kunalnandi · 05-01-2009, 04:32 AM

Hello All,

I want memory log of my application and for that i want any system function that will give information similar to /proc/<My_App_Pid>/status.

basically i need all Virtual memory values like VmSize, VmPeak, VmRSS etc. and number of threads running.

Regards
Kunal Nandi

tommylovell · 05-01-2009, 09:16 PM

Nope. You don't need one. The proc filesystem is "in storage" and ascii, so a standard read of it is really efficient.
All of the utilities that I've ever seen that access the proc filesystem use standard open/read/close.

Here's a function that'll work.

Code:

static int read_proc_file(char *file_name, char *buffer, int size)
{
        int num_bytes_read, fp;

        fp = open(file_name, O_RDONLY);
        if (!fp) {
                syslog(LOG_ERR, "Failed to open %s: %s\n", file_name,
                        strerror(errno));
                return -1;
        }

        num_bytes_read = read(fp, buffer, size);
        if (num_bytes_read < 0) {
                syslog(LOG_ERR, "Failed to read %s\n", file_name);
                close(fp);
                return -1;
        }

        close(fp);
        return num_bytes_read;
}

kunalnandi · 05-02-2009, 01:22 AM

actually i hv already tried this before but, i was looking for some system function any ways thanks for your reply

Quote:

Originally Posted by tommylovell

Nope. You don't need one. The proc filesystem is "in storage" and ascii, so a standard read of it is really efficient.
All of the utilities that I've ever seen that access the proc filesystem use standard open/read/close.

Here's a function that'll work.

Code:

static int read_proc_file(char *file_name, char *buffer, int size)
{
        int num_bytes_read, fp;

        fp = open(file_name, O_RDONLY);
        if (!fp) {
                syslog(LOG_ERR, "Failed to open %s: %s\n", file_name,
                        strerror(errno));
                return -1;
        }

        num_bytes_read = read(fp, buffer, size);
        if (num_bytes_read < 0) {
                syslog(LOG_ERR, "Failed to read %s\n", file_name);
                close(fp);
                return -1;
        }

        close(fp);
        return num_bytes_read;
}

Regards
Kunal Nandi