- stdin - stdout - stderr - tee - xargs stdin stuff a program chews up wc < file1.txtsome programs don’t accept data from stdin stdoutstuff a program spits out ls > ls.txt ls 1> ls.txt stderrwhere a program complains ls bob 2> ls.txtredirects stderr to ls.txt   Both stdout and stderror go to the conso…

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copy, move, delete wildcards find files based on type, size & date tar, cpio, dd bzip2, gunzip copy - cp - cp -R; -r; --recursive example: - cp 123.txt 234.txt - cp -R folder1/ folder2/ move - mv example: - mv folder1/ folder2/ - mv folder1/789.txt ./ delete / remove - rm - rm -f - rm -rf example: - rm file.abc - …

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  cat, cut, expand, fmt, head, od, join, nl, paste, pr, sed, sort, split, tail, tr unexpand, uniq, wc, xargs cat concatenate files and print on the standard output Flags: -n number all output lines -T, --show-tabs display TAB characters as ^I -E, --show-ends display $ at end of each line# cat hello.txt hello2.txt…

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Bash Shell environment PATH environment variables history completion commands The shell that a user uses is defines in /etc/passwd testuser:x:1001:1001:testuser user:/home/testuser:/bin/bash The settings for how bash behaves are stored in a couple different places /etc/profile# /etc/profile: system-wide .profile file …

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rpm rpm2cpio alien yum /etc/yum.conf /etc/yum.repos.d yum downloader yum is alike like apt-get is in debian like distribsyum install open-ssh clients[root@localhost ovidiu]# yum install openssh-clients Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirrors.ch-center.com * extras: mirr…

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what are shared libraries determining associated libraries configuring system ldd, lddconfig ld.so.cache, ld.so.conf.d A shared library or shared object is a file that is intended to be shared by executable files and further shared objects files. Modules used by a program are loaded from individual shared objects into…

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