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An advanced possibility to count the lines of code like in #8394
it recursively searches your project's directories and sum the lines of every source [.c or .h]. Then it gives you the total.
Bash function copies a file prefixed with a version number to a subdirectory
Counts the number of new emails in the post office (or wherever mail is set up to check).
The same thing using only Bash built-in's.
For readability I've kept the variables out, but it could me made extremely more compact (and totally unreadable!) by stuffing everything inside the single echo command.
This gives a very rough estimate of how many pages your text files will print on. Assumes 60 lines per page, and does not take long lines into account.
Download a bunch of random animated gifs from http://gifbin.com/
Center the output text in max line length of buffered output pipe;
If you have a folder with thousand of files and want to have many folder with only 100 file per folder, run this.
It will create 0/,1/ etc and put 100 file inside each one.
But find will return true even if it don't find anything ...
A simple command to find the total number of subdirectories in current directory starting with specific name.
usage:
where COMMIT
for instance:
where 1178c5950d321a8c5cd8294cd67535157e296554
where HEAD~5
Kills all process that belongs to the user that runs it - excluding bash, sshd (so putty/ssh session will be spared). The bit that says grep -vE "..." can be extended to include ps line patterns that you want to spare.
If no process can be found on the hitlist, it will print # NOTHING TO KILL. Otherwise, it will print # KILL EM ALL, with the cull list.
Use bc for decimals...
This Anti-TarBomb function makes it easy to unpack a .tar.gz without worrying about the possibility that it will "explode" in your current directory. I've usually always created a temporary folder in which I extracted the tarball first, but I got tired of having to reorganize the files afterwards. Just add this function to your .zshrc / .bashrc and use it like this;
atb arch1.tar.gz
and it will create a folder for the extracted files, if they aren't already in a single folder.
This only works for .tar.gz, but it's very easy to edit the function to suit your needs, if you want to extract .tgz, .tar.bz2 or just .tar.
More info about tarbombs at http://www.linfo.org/tarbomb.html
Tested in zsh and bash.
UPDATE: This function works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in zsh (not working in bash):
atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t(ar.gz||ar.bz2||gz||bz||ar)} && tar xf $1 -C ${1%.t(ar.gz||ar.bz2||gz||bz||ar)}; fi ;}
UPDATE2: From the comments; bepaald came with a variant that works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in bash:
atb() {shopt -s extglob ; l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)} && tar xf $1 -C ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)}; fi ; shopt -u extglob}
command was too long...
this is the complete command:
fname=$1; f=$( ls -la $fname ); if [ -n "$f" ]; then fsz=$( echo $f | awk '{ print $5 }' ); if [ "$fsz" -ne "0" ]; then nrrec=$( wc -l $fname | awk '{ print $1 }' ); recsz=$( expr $fsz / $nrrec ); echo "$recsz"; else echo "0"; fi else echo "file $fname does not exist" >&2; fi
First the input is stored in var $fname
The file is checked for existance using "ls -lart".
If the output of "ls -lart" is empty, the error message is given on stderr
Otherwise the filelength is taken from the output of "ls -lart" (5th field)
With "wc -l" the number of records (or lines) is taken.
The record size is filelength devided by the number of records.
please note: this method does not take into account any headers, variable length records and only works on ascii files where the records are sperated by 0x0A (or 0x0A/0x0D on MS-DOS/Windows).