Bash Scripting , I recently came across a situation where i had to perform certain task on a random file ( of particular extension ) picked up from a directory structure. My OS was linux and so i went for Bash Scripting !<\/p>\n
The\u00a0<\/span>script\u00a0<\/span>informs\u00a0<\/span>the\u00a0<\/span>performers\u00a0<\/span>what\u00a0<\/span>they\u00a0<\/span>are\u00a0<\/span>supposed\u00a0<\/span>to\u00a0<\/span>say\u00a0<\/span>and\u00a0<\/span>do in Bash Scripting. <\/span>A\u00a0<\/span>computer\u00a0<\/span>script\u00a0<\/span>informs <\/span>the\u00a0<\/span>pc\u00a0<\/span>what\u00a0<\/span>it\u00a0<\/span>could\u00a0<\/span>or\u00a0<\/span>should\u00a0<\/span>say.We’re telling the Bash shell what to do in\u00a0 the framework of Bash scripts. A Bash script is a plain text file containing a number of commands.<\/span><\/p>\n I played with some known ( to me, obviously ) commands from my PS1 prompt before i nailed it down.<\/p>\n SearchFolder=”\/home\/sai\/cPrograms” Line by Line Logic<\/p>\n SearchFolder=”\/home\/sai\/cPrograms”<\/p>\n This sets the parent folder of the directory tree to be searched, i.e the scan starts from this directory and prgresses inward for Bash Scripting.<\/p>\n NumberOfcFiles=`find $SearchFolder -iname “*.c” | wc -l`<\/p>\n Variable NumberOfcFiles speaks for itself. find makes a list of .c files and “wc -l” counts them for me.<\/p>\n rNumber=$[ ( $RANDOM % $NumberOfcFiles ) + 1 ]<\/p>\n $RANDOM is a bash variable that throws pseudo random numbers every time its called ( Thanks to BASH again ! ). RightHandSide of the above code is to obtain a random number within the 1-$NumberOfcFiles range. i.e if there are 100 files, rNumber will be a random number with in the range 1 – 100.<\/p>\n rFile=`find $SearchFolder -iname “*.c” | sed -n “$rNumber p”` This simply picks $rNumber th file from the “find” list and ls prints it on your screen.<\/p>\n Wasn’t that fun ??<\/p>\n go for quick reference on click here<\/a><\/p>\n reference sites :wikipedia<\/a><\/p>\n
\nNumberOfcFiles=`find $SearchFolder -iname “*.c” | wc -l`
\nrNumber=$[ ( $RANDOM % $NumberOfcFiles ) + 1 ]
\nrFile=`find $SearchFolder -iname “*.c” | sed -n “$rNumber p”`
\nls $rFile<\/p>\n
\nls $rFile<\/p>\n