crash utility help page:  sys


NAME
  sys - system data

SYNOPSIS
  sys [-c [name|number]] config

DESCRIPTION
  This command displays system-specific data.  If no arguments are entered,
  the same system data shown during crash invocation is shown.

    -c [name|number]  If no name or number argument is entered, dump all
                      sys_call_table entries.  If a name string is entered,
                      search the table for all entries containing the string.
                      If a number is entered, the table entry associated with
                      that number is displayed.  If the current output radix
                      has been set to 16, the system call numbers will be 
                      displayed in hexadecimal.
    config            If the kernel was configured with CONFIG_IKCONFIG, then
                      dump the in-kernel configuration data.
    -panic            Panic a live system.  Requires write permission to
                      /dev/mem.  Results in the crash context causing an
                      "Attempted to kill the idle task!" panic.  (The dump
                      will indicate that the crash context has a PID of 0).

EXAMPLES
  Display essential system information:

    crash> sys
          KERNEL: vmlinux.4
        DUMPFILE: lcore.cr.4
            CPUS: 4
            DATE: Mon Oct 11 18:48:55 1999
          UPTIME: 10 days, 14:14:39
    LOAD AVERAGE: 0.74, 0.23, 0.08
           TASKS: 77
        NODENAME: test.mclinux.com
         RELEASE: 2.2.5-15smp
         VERSION: #24 SMP Mon Oct 11 17:41:40 CDT 1999
         MACHINE: i686  (500 MHz)
          MEMORY: 1 GB

  Dump the system configuration data (if CONFIG_IKCONFIG):

    crash> sys config
    #
    # Automatically generated make config: don't edit
    # Linux kernel version: 2.6.16
    # Mon Apr 10 07:58:06 2006
    #
    CONFIG_X86_64=y
    CONFIG_64BIT=y
    CONFIG_X86=y
    CONFIG_SEMAPHORE_SLEEPERS=y
    CONFIG_MMU=y
    CONFIG_RWSEM_GENERIC_SPINLOCK=y
    CONFIG_GENERIC_CALIBRATE_DELAY=y
    CONFIG_X86_CMPXCHG=y
    CONFIG_EARLY_PRINTK=y
    CONFIG_GENERIC_ISA_DMA=y
    CONFIG_GENERIC_IOMAP=y
    CONFIG_ARCH_MAY_HAVE_PC_FDC=y
    CONFIG_DMI=y
    ...

  Dump the system call table:

    crash> sys -c
    NUM  SYSTEM CALL                FILE AND LINE NUMBER
      0  sys_ni_syscall             ../kernel/sys.c: 48
      1  sys_exit                   ../kernel/exit.c: 404
      2  sys_fork                   ../arch/i386/kernel/process.c: 771
      3  sys_read                   ../fs/read_write.c: 117
      4  sys_write                  ../fs/read_write.c: 146
      5  sys_open                   ../fs/open.c: 754
      6  sys_close                  ../fs/open.c: 839
      7  sys_waitpid                ../kernel/exit.c: 503
      8  sys_creat                  ../fs/open.c: 789
      9  sys_link                   ../fs/namei.c: 1213
     10  sys_unlink                 ../fs/namei.c: 1074
     11  sys_execve                 ../arch/i386/kernel/process.c: 806
    ...

  Find the system call number of the select system call:

    crash> sys -c select
    NUM  SYSTEM CALL                FILE AND LINE NUMBER
     65  sys_select                 ../fs/select.c: 259
 
    If the current output radix has been set to 16, the system call numbers
    will be displayed in hexadecimal.