Commands tagged arithmetic (6)

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type partial command, kill this command, check something you forgot, yank the command, resume typing.
Example : $ vim /etc/fstab ## damn $ $ sudo ## like a boss. Example 2 : $ sudo vim /root/bin/ ##uh... autocomplete doesn't work... $ $ sudo ls /root/bin ##ah! that's the name of the file! $ sudo vim /root/bin/ ##resume here! Thanks readline!

Run skype using your GTK theme
I use this to make skype blend better into my desktop :) --disable-cleanlooks might not be nescessary to achieve the wanted effect.

Check if a command is available in your system
Usefull to detect if a commad that your script relies upon is properly installed in your box, you can use it as a function function is_program_installed() { type "$1" >/dev/null } Invoke it and check the execution code is_program_installed "dialog" if [ ! $? -eq 0 ]; then echo "dialog is not installed" exit 1 fi

reverse order of file

Crash bash, in case you ever want to for whatever reason
This is a very hackish way to do it that I'm mainly just posting for fun, and I guess technically can more accurately be said to result in undefined behavior. What the command does is tell the shell to treat libpng like it's a shell plugin (which it's most certainly not) and attempt to install a "png_create_read" command from the library. It looks for the struct with the information about the command; since it's always the command name followed by "_struct", it'll look for a symbol called "png_create_read_struct". And it finds it, since this is the name of one of libpng's functions. But bash has no way to tell it's a function instead of a struct, so it goes ahead and parses the function's code as if it was command metadata. Inevitably, bash will attempt to dereference an invalid pointer or whatever, resulting in a segfault.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Use top to monitor only all processes with the same name fragment 'foo'
top accecpts a comma separated list of PIDs.

Console clock
Shows a simple clock in the console -t param removes the watch header Ctrl-c to exit

Replace Solaris vmstat numbers with human readable format
% cat ph-vmstat.awk # Return human readable numbers function hrnum(a) { b = a ; if (a > 1000000) { b = sprintf("%2.2fM", a/1000000) ; } else if (a > 1000) { b = sprintf("%2.2fK", a/1000) ; } return(b) ; } # Return human readable storage function hrstorage(a) { b = a ; if (a > 1024000) { b = sprintf("%2.2fG", a/1024/1024) ; } else if (a > 1024) { b = sprintf("%2.2fM", a/1024) ; } return(b) ; } OFS=" " ; $1 !~ /[0-9].*/ {print} $1 ~ /[0-9].*/ { $4 = hrstorage($4) ; $5 = hrstorage($5) ; $9 = hrnum($9) ; $10 = hrnum($10) ; $17 = hrnum($17) ; $18 = hrnum($18) ; $19 = hrnum($19) ; print ; }

Get length of current playlist in xmms2


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