Különbségek

A kiválasztott változat és az aktuális verzió közötti különbségek a következők.

--- linux [2020/05/19 10:05] – admin
+++ linux [2024/03/12 16:57] (aktuális) – admin
@@ Sor 1: / Sor 1: @@
 ===== Linux okosságok =====
+==== Dátum figyelés ====
+  function date_diff()
+  {
+    date='2020-08-12T16:00:10'
+    epoch=$(date -d "$date" +%s)
+    if [ "$epoch" -lt "$(date -d '1 minute ago' +%s)" ] ; then
+  #[[ "$(date -d '2024-02-01 17:26:00' +%s)" -lt "$(date +%s)" ]] && echo elmult || echo nem
+        echo At least 3 days ago
+    else
+        echo Too recent
+    fi
+  }
+==== Reboot, ha nem megy a szabályos reboot ====
+  # echo s > /proc/sysrq-trigger
+  # echo u > /proc/sysrq-trigger
+  # echo s > /proc/sysrq-trigger
+  # echo b > /proc/sysrq-trigger
+This requests the kernel to do:
+emergency sync of the block devices;
+mount readonly of all filesystems;
+again a sync;
+force an immediate boot; (you can also use o for poweroff)
+==== dm-* device-ok felderítése ====
+  find /dev/ -name "dm-*" -exec readlink -n {} \; -exec echo " -->" {} \;
+==== SCSI (re)scan ====
+  #!/bin/sh
+  for I in `ls -d /sys/class/scsi_device/*`; do
+        echo ${I}
+        echo "1" > ${I}/device/rescan
+  done
+  #!/bin/sh
+  for I in `ls -d /sys/class/scsi_host/host*`; do
+        echo ${I}
+        echo "- - -" > ${I}/scan
+  done
+==== Yum-mal telepített csomagok listázása log fájlból ====
+  cat /var/log/yum.log | sed "s#.\+: \?\(.\+\)#\1#" | sort
+==== Disk perf. teszt DD-vel ====
+<file>
+#!/bin/bash
+echo -n "Fajl nev: "
+read FNEV
+echo -n "Blokk meret (Byte): "
+read BS
+echo -n "Fajl meret (MByte): "
+read FS
+COUNT=$((FS*1024*1024 / $BS))
+COUNT=$(echo $COUNT | sed 's/\..*$/g/')
+echo -n "Diszk irasa (dd if=/dev/zero of=$FNEV bs=$BS count=$COUNT)… "
+SEC=$(timex dd if=/dev/zero of=$FNEV bs=$BS count=$COUNT 2>&1 | awk '/real/{print $2}' | awk -F'.' '{print $1}')
+echo "$(($FS / $SEC)) MB/s"
+</file>
 ==== BOOT probléma ====
@@ Sor 5: / Sor 72: @@
 GRUB menüben a "quiet" paraméter helyére "dracut rdshell"-t betenni
+==== ~/.vimrc ====
+  set number background=dark
+  syntax on
+  highlight Comment    ctermfg=119
+  highlight Identifier ctermfg=99AA00
+  set ts=4 sw=4
+  undolevels=1000
 ==== RAID megoldások ====
@@ Sor 28: / Sor 103: @@
   lvdisplay -C -S lv_role=snapshot
-==== SSH kilép aciklusból az első futás után ====
+==== sudo jog másik userhez ====
+  non-root-user ALL = (appuser) NOPASSWD: ALL
-  ssh -n ...
 ==== NMON adatgyűjtés ====
@@ Sor 52: / Sor 128: @@
 nmon -f -s $INTERVAL -c $SAMPLES
 </file>
-==== Ismétlődő sorok számolása ====
-  cat file | sed 's/([^(]*)$/,&/' | awk -F'[,]' '{a[$2]++}END{for(k in a) print $1,k,$3,"("a[k]"x)"}'
-==== User input default értékkel ====
-  DEFAULT="Semmit"
-  read -e -p "Mit akarsz?" -i "$DEFAULT" VALTOZO
-  VALTOZO="${VALTOZO:-$DEFAULT}"
-==== /dev/stdin üres-e? (Van-e adat a pipe-ban?) ====
-  [ ! -t 0 ]
-==== Bekezdésre greppelés Linux alatt (AIX: grep -p) ====
-  awk 'BEGIN{RS=ORS="\n\n";FS=OFS="\n"}/Storage Slots/
 ==== Email címek extraktálása AIX alatt ====
@@ Sor 110: / Sor 169: @@
 # Get current swap usage for all running processes
 # Erik Ljungstrom 27/05/2011
+echo "Swappiness: $(cat /proc/sys/vm/swappiness)"
 SUM=0
 OVERALL=0
@@ Sor 126: / Sor 186: @@
 </file>
-==== Sztringek hexa értelmezésének kiküszöbölése ====
-Pl:
-  $((10#`date +%H`))
-==== A grep "-o" kapcsolójának kiváltása perl-lel ====
-  perl -lne '/reguláris kifejezés/ && print $&'
 ==== Törölt fájlok, amik nem szabadították még fel a helyet ====
   lsof |(sed 1q; grep deleted)
-==== BASH változó manipulációk ====
+==== Hosszú processz végeztéről értesítő email ====
-^Syntax^Meaning^
+<file>
-|${#var} | String length (number of characters in $var).|
+#!/bin/bash
-|${var%%^%%} | Uppercase first alphanumeric character in $var.|
+MAILTO="rvenyige@pcs.hu,pagoston@pcs.hu"
-|${var%%^^%%} | Uppercase alphanumeric characters in $var.|
+SSH="ssh -i /home/pagoston/.ssh/id_rsa pagoston@sapeltora "
-|${var%%^^%%[p,g]} | Uppercase alphanumeric characters in $var matching p or g.|
+while [ $($SSH "ps -ef | awk '{print $2}'" | grep -c "$1") -gt 0 ]; do
-|${parameter?err_msg},${parameter:?err_msg} | If parameter set, use it, else print err_msg and abort the script with an exit status of 1. Both forms nearly equivalent. The : makes a difference only when parameter has been declared and is null.|
+        sleep 60
-|${parameter-default},${parameter:-default} | If parameter not set, use default. ${parameter-default} and ${parameter:-default} are almost equivalent. The extra : makes a difference only when parameter has been declared, but is null.|
+done
-|${parameter=default},${parameter:=default} | If parameter not set, set it to default. Both forms nearly equivalent. The : makes a difference only when $parameter has been declared and is null.|
+echo Lefutott | mail -s "Process $1 lefutott (${hostname})" $MAILTO
-|${parameter+alt_value},${parameter:+alt_value} | If parameter set, use alt_value, else use null string. Both forms nearly equivalent. The : makes a difference only when parameter has been declared and is null.|
+</file>
-|${var#Pattern} | Remove from $var the shortest part of $Pattern that matches the front end of $var.|
-|${var##Pattern} | Remove from $var the longest part of $Pattern that matches the front end of $var.|
-|${var%Pattern} | Remove from $var the shortest part of $Pattern that matches the back end of $var.|
-|${var%%%%Pattern} | Remove from $var the longest part of $Pattern that matches the back end of $var.|
-|${var:pos} | Variable var expanded, starting from offset pos.|
-|${var:pos:len} | Expansion to a max of len characters of variable var, from offset pos.|
-|${var/Pattern/Replacement} | First match of Pattern, within var replaced with Replacement. If Replacement is omitted, then the first match of Pattern is replaced by nothing, that is, deleted.|
-|${var%%//%%Pattern/Replacement} | Global replacement. All matches of Pattern, within var replaced with Replacement. If Replacement is omitted, then all occurrences of Pattern are replaced by nothing, that is, deleted.|
-|${var/#Pattern/Replacement} | If prefix of var matches Pattern, then substitute Replacement for Pattern.|
-|${var/%Pattern/Replacement} | If suffix of var matches Pattern, then substitute Replacement for Pattern.|
-|${!varprefix*},${!varprefix@} | Matches names of all previously declared variables beginning with varprefix.|
-forrás: [[http://tldp.org/LDP/abs/html/parameter-substitution.html]]
+==== processz elrejtése a PS kimenetből ====
-==== Gyakori BASH RC kódok ====
-^Exit Code Number	^Meaning	^Example	^Comments^
+<file>
-|1	|Catchall for general errors	|let "var1 = 1/0"	|Miscellaneous errors, such as "divide by zero" and other impermissible operations|
+/* https://unix.stackexchange.com/a/403918/119298
-|2	|Misuse of shell builtins (according to Bash documentation)	|empty_function() {}	|Missing keyword or command|
+ * capture calls to a routine and replace with your code
-|126	|Command invoked cannot execute	|/dev/null	|Permission problem or command is not an executable|
+ * gcc -Wall -O2 -fpic -shared -ldl -o shim_main.so shim_main.c
-|127	|"command not found"	|illegal_command	|Possible problem with $PATH or a typo|
+ * LD_PRELOAD=/.../shim_main.so theprogram theargs...
-|128	|Invalid argument to exit	|exit 3.14159	|exit takes only integer args in the range 0 - 255 (see first footnote)|
+ */
-|128+n	|Fatal error signal "n"	|kill -9 $PPID of script	|$? returns 137 (128 + 9)|
+#define _GNU_SOURCE /* needed to get RTLD_NEXT defined in dlfcn.h */
-|130	|Script terminated by Control-C	|Ctl-C	|Control-C is fatal error signal 2, (130 = 128 + 2, see above)|
+#include <stdlib.h>
-|255*	|Exit status out of range	|exit -1	|exit takes only integer args in the range 0 - 255|
+#include <stdio.h>
+#include <string.h>
+#include <signal.h>
+#include <unistd.h>
+#include <dlfcn.h>
-==== Hiba csatorna színezése ====
+typedef int (*pfi)(int, char **, char **);
+static pfi real_main;
-   $ parancs 2> >(while read line; do echo -e "\e[01;31m$line\e[0m"; done)
+/* copy argv to new location */
+char **copyargs(int argc, char** argv){
-==== Bash színkódok törlése szövegből ====
+    char **newargv = malloc((argc+1)*sizeof(*argv));
+    char *from,*to;
+    int i,len;
-  sed "s,\x1B\[[0-9;]*[a-zA-Z],,g"
+    for(i = 0; i<argc; i++){
+        from = argv[i];
+        len = strlen(from)+1;
+        to = malloc(len);
+        memcpy(to,from,len);
+        memset(from,'\0',len);    /* zap old argv space */
+        newargv[i] = to;
+        argv[i] = 0;
+    }
+    newargv[argc] = 0;
+    return newargv;
+}
-==== Dátumos prompt képernyőmentéses dokumentáláshoz ====
+static int mymain(int argc, char** argv, char** env) {
+    fprintf(stderr, "main argc %d\n", argc);
+    return real_main(argc, copyargs(argc,argv), env);
+}
-  export PS1='[\u@\h \W] \D{%F %T}\n\$ '
+int __libc_start_main(pfi main, int argc,
+                      char **ubp_av, void (*init) (void),
+                      void (*fini)(void),
+                      void (*rtld_fini)(void), void (*stack_end)){
+    static int (*real___libc_start_main)() = NULL;
-==== Terminál kurzor pozícionálás ====
+    if (!real___libc_start_main) {
+        char *error;
-- Position the Cursor:
+        real___libc_start_main = dlsym(RTLD_NEXT, "__libc_start_main");
-  \033[<L>;<C>H
+        if ((error = dlerror()) != NULL) {
-     Or
+            fprintf(stderr, "%s\n", error);
-  \033[<L>;<C>f
+            exit(1);
-  puts the cursor at line L and column C.
+        }
-- Move the cursor up N lines:
+    }
-  \033[<N>A
+    real_main = main;
-- Move the cursor down N lines:
+    return real___libc_start_main(mymain, argc, ubp_av, init, fini,
-  \033[<N>B
+            rtld_fini, stack_end);
-- Move the cursor forward N columns:
-  \033[<N>C
-- Move the cursor backward N columns:
-  \033[<N>D
-- Clear the screen, move to (0,0):
-  \033[2J
-- Erase to end of line:
-  \033[K
-- Save cursor position:
-  \033[s
-- Restore cursor position:
-  \033[u
-==== "Homokóra" - progress icon ====
-v1:
-<file>
-a=1
-sp="/-\|"
-echo -n ' '
-while true
-do
-    printf "\b${sp:a++%${#sp}:1}"
-done
-</file>
-v2:
-<file>
-spinner()
-{
-    local pid=$1
-    local delay=0.75
-    local spinstr='|/-\'
-    while [ "$(ps a | awk '{print $1}' | grep $pid)" ]; do
-        local temp=${spinstr#?}
-        printf " [%c]  " "$spinstr"
-        local spinstr=$temp${spinstr%"$temp"}
-        sleep $delay
-        printf "\b\b\b\b\b\b"
-    done
-    printf "    \b\b\b\b"
 }
-</file>
-==== Színkódok és sorvég karakterek kivágása szövegből ====
-A ^M-et így: CTRL+V, CTRL+M !!
-  sed -i -e 's/\x1b\[[0-9;]*m//g' -e 's/^M//g' file
-==== Parancsok csoportosítása ====
-Új shellben:
-  (parancs1)
-Aktuális shellben:
-  { parancs1; }
-==== Hosszú processz végeztéről értesítő email ====
-<file>
-#!/bin/bash
-MAILTO="rvenyige@pcs.hu,pagoston@pcs.hu"
-SSH="ssh -i /home/pagoston/.ssh/id_rsa pagoston@sapeltora "
-while [ $($SSH "ps -ef | awk '{print $2}'" | grep -c "$1") -gt 0 ]; do
-        sleep 60
-done
-echo Lefutott | mail -s "Process $1 lefutott (${hostname})" $MAILTO
 </file>
@@ Sor 278: / Sor 278: @@
   * [[https://ef.gy/forwarding-ipv4-to-ipv6|Forwarding IPv4 Ports to IPv6-only Hosts]]
   * [[https://www.techrepublic.com/article/how-to-setup-two-factor-authentication-in-linux|Két faktoros authentikáció linuxon]]
+  * [[https://access.redhat.com/articles/17054|How do I find the FC ID (WWN) of a scsi device/LUN on Red Hat Enterprise Linux?]]

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Különbségek