Questions tagged [proc]
procfs (or the proc filesystem) is a special filesystem in UNIX-like operating systems that presents information about processes and other system information in a hierarchical file-like structure
577 questions
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Why is there a discrepancy between the stack address in /proc/PID/maps vs. /proc/PID/stat?
Why does there appear to be a discrepancy between a process stack address within /proc/PID/maps compared to the stack start address within /proc/PID/stat, where the latter is a smaller subset of the ...
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Discrepancies for entries for the same map in different /proc/*/smaps files
The snippet below:
shows statistics for what appears to be the exact same memory mapping: same device number, same inode, same offset, same length (0x7f8656e78000-0x7f8656cbb000 = 0x7f2f4ef6a000-...
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How to interpret the refcnt field in /proc/crypto?
Here's an example /proc/crypto entry:
name : md5
driver : md5-generic
module : kernel
priority : 0
refcnt : 1
selftest : passed
internal : no
type : shash
...
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OpenBSD process maps
I am using OpenBSD 7.7.
So I know that procfs is not mounted on /proc, and I need to use sysctl to fetch process maps. But this fails as I am not running as a root user. The secure level is set to 1 ...
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Recovering text of Unsaved document from process memory? (frozen Xed window - process still "running" but in Sleeping status)
The window of my text editor Xed froze with Unsaved documents just as I was doing 'File'->'Save as...' to save them... [How ironic.]
Since the process still exists, I am trying to recover the text ...
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How can I find location of PRI in /proc
I have sshd with PID of 1957:
mohsen@debian:~$ ps ax -o pid,nice,pri,cmd |grep 1957
1957 -2 21 sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups
According to above, my nice number is -2 ...
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reading stdout from /proc [duplicate]
I'm running the following C program
// hello.c
#include <stdio.h>
#include <unistd.h>
int main() {
while (1) {
printf("Hello\n");
fflush(stdout);
sleep(1);
}
...
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Finding actual memory usage of process
I have seen similar questions 1, 2, and understand the difference between RSS/VSZ.
I've some uses of mmap'ing distinct virtual memory regions to the same underlying physical memory.
In this case, /...
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Why are some symlinks unreadable when their target is readable?
On Linux, I'm looking at /proc/1/cwd. This symlink is not readable as a normal user:
$ ls /proc/1/cwd
ls: cannot access '/proc/1/cwd': Permission denied
But /proc/1 is accessible:
$ ls /proc/1
<...
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In /proc/$PID/smaps in the VmFlags what is the difference between "readable" and "may read"?
The man page describes the meaning of the VmFlags:
The "VmFlags" line (available since Linux 3.8) represents
the kernel flags associated with the virtual memory ...
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Why is dd unable to read /proc/pid/mem?
Why is GNU Coreutil's dd unable to read /proc/pid/mem? PHP is able to read it, check this:
$ dd if=/proc/357668/mem bs=100 skip=93824992231424 count=1 iflag=fullblock
dd: /proc/357668/mem: cannot skip ...
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Is there a linux kernel interface (/proc) that counts kernel error log messages?
The comand dmesg --level=emerg,alert,crit,err lists all error messages with a high severity.
I wondered for monitoring purposes whether the count of messages is somehow exposed in the /proc filesystem....
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Are reads of /proc/pid/environ atomic in Linux 6.x (e.g: 6.1.99)?
When a process execs, looking at kernel code for environ_read(), it seems that if the mm_struct doesn't yet exist / is null or the env_end member of that mm_struct is null, environ_read() will return ...
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Unexpected behavior of 'some' PSI CPU metric
I am trying to understand the meaning of the "some" row of the Linux PSI metric for CPU. The Linux documentation (https://github.com/torvalds/linux/blob/master/Documentation/accounting/psi....
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/proc/pid exists but does pid not found in ps
I am seeing a very odd behavior.
/proc/1154/cmdline exists, and kill -0 1154 succeeds,
but ps -ef | grep 1154 and ls /proc | grep 1154 do not show anything.
1154 was a postgres process in the middle ...
