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How to list just one repo with yum. First I disable all repo, second I enable just the repo that I want to list.
I was looking for the fastest way to create a bunch of ansi escapes for use in echo -e commands throughout a lot of my shell scripts. This is what I came up with, and I actually stick that loop command in a function and then just call that at the beginning of my scripts to not clutter the environment with these escape codes, which can wreck havok on my terminal when I'm dumping the environment. More of a cool way to store escape ansi codes in an array. You can echo them like:
$ echo -e "${CC[15]}This text is black on bright green background."
I usually just use with a function:
$ # setup_colors - Adds colors to array CC for global use
$ # 30 - Black, 31 - Red, 32 - Green, 33 - Yellow, 34 - Blue, 35 - Magenta, 36 - Blue/Green, 37 - White, 30/42 - Black on Green '30\;42'
$ function setup_colors(){ declare -ax CC; for i in `seq 0 7`;do ii=$(($i+7));CC[$i]="\033[1;3${i}m";CC[$ii]="\033[0;3${i}m";done;CC[15]="\033[30;42m"; export R='\033[0;00m';export X="\033[1;37m"; };
$ export -f setup_colors
CC[15] has a background of bright green which is why it is separate. R resets everything, and X is my default font of bright white.
$ CC[15]="\033[30;42m"; R=$'\033[0;00m'; X=$'\033[1;37m'
Those are just my favorite colors that I often use in my scripts. You can test which colors by running
$ for i in $(seq 0 $((${#CC[@]} - 1))); do echo -e "${CC[$i]}[$i]\n$R"; done
See: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html for more usage.
This is just a slight alternative that wraps all of #7917 in a function that can be executed
If you want to operate on a set of items in Bash, and at least one of them contains spaces, the `for` loop isn't going to work the way you might expect. For example, if the current dir has two files, named "file" and "file 2", this would loop 3 times (once each for "file", "file", and "2"):
$ for ITEM in `ls`; do echo "$ITEM"; done
Instead, use a while loop with `read`:
$ ls | while read ITEM; do echo "$ITEM"; done
Shows all block devices in a tree with descruptions of what they are.
You can tell GCC to automatically select optimization commands and produce optimized code for the local machine (the one compiling the code), but you can't normally see what switches have been selected and used unless you append a "-v" and pause compilation.
pushd and popd are your friends, but sometimes they're just incompatible with the way one works...
Two shell functions:
bm bookmarkname - "bookmarks" the current directory, just 'cd $BMbookmarkname' to return to it.
forget bookmarkname - unsets the 'bookmarkname' variable. It isn't mandatory, they cease to exist when the session ends.
Trace python statement execution and syscalls invoked during that simultaneously