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8
votes
1answer
1k views

How to get current buffer's filename in emacs?

One of the main features I miss about Vim, is that it always saves the filename of the current file in the % buffer (more info). That allows launching commands easily like: ;; compile current file :! ...
2
votes
1answer
212 views

awk function with a number parameter for the column you want to print

I want to use my awk shortcut as a function, so that I can pass the column number which then prints me the output. My aliases are: alias A="| awk '{print \$1}' alias G="| grep -i' Instad of typing: ...
2
votes
1answer
83 views

Restoring an option at the end of a function in zsh

I'm writing a zsh shell function (as opposed to a script) where I would really like the extended_glob option to be enabled. But since the function runs in the caller's context, I don't want to clobber ...
3
votes
3answers
706 views

Infinitely Nested Directories

Let me start off by saying this is a Mac Terminal I'm using. Not Linux, but I assumed I would get the best answers here as it has to do with Unix and the command line not really anything about Mac ...
1
vote
1answer
222 views

Switching source and destination (or undoing the mv, cp operation)

mv or cp commands both expect source and destination as arguments. In case you want to undo the change you made, or just change the source and destination you supplied before, what is the quickest ...
2
votes
1answer
295 views

Why do Unix-like systems execute a new process when calling a new function?

Why do Unix-like systems execute a new process when calling a function rather than a dynamic library? Creating a new process is costly in terms of performance when compared to calling a dynamic ...
2
votes
0answers
358 views

How to enable `sudo` with custom functions?

Recently I learned you can enable sudo for custom aliases as follows: alias sudo='sudo ' # note: the space is required! The reason this works is the following: If the last character of the ...
1
vote
1answer
601 views

How to understand the result returned by “nm” command

I used nm command to inspect the function names in a .so library. And the result I got is like this: 00009634 T _Z24ICTCLAS_ParagraphProcessPKciPc9eCodeTypeb 00009764 T ...
4
votes
4answers
1k views

How can I pass a command line argument into a shell script?

I know that shell scripts just run commands as if they were executed in at the command prompt. I'd like to be able to run shell scripts as if they were functions... That is, taking an input value or ...
1
vote
2answers
929 views

Script to create files in a template

I just wrote a function in my ~/.bashrc that will let me create a folder for a new website with one command. The function looks like this: function newsite() { mkcd "$*" # mkdir and cd into it ...
137
votes
10answers
12k views

In Bash, when to alias, when to script, and when to write a function?

It's taken me almost 10 years of Linux usage to ask this question. It was all trial and error and random late-night internet surfing. But people shouldn't need 10 years for this. If I were just ...
7
votes
7answers
3k views

Doing simple math on the command line using bash functions: $1 divided by $2 (using bc perhaps)

Sometimes I need to divide one number by another. It would be great if I could just define a bash function for this. So far, I am forced to use expressions like echo 'scale=25;65320/670' | bc but ...
7
votes
2answers
621 views

How do I redefine a bash function in terms of old definition?

Is there any way I can redefine a bash function in terms of its old definition? For example I would like to add the following block of code to the preamble of the function command_not_found_handle (), ...
1
vote
3answers
184 views

What does the “(8)” in fsck(8) mean?

*nix commands (and functions?) have a number with them, like fsck(8), killall(1), etc. What does the number mean?
12
votes
4answers
4k views

Can I “export” functions in bash?

source some_file some_file: doit () { echo doit $1 } export TEST=true If I source some_file the function "doit" and the variable TEST are available on the command line. But running this script: ...
3
votes
3answers
2k views

How to pass a string parameter on bash function?

I have this code that does work: get_parameter () { echo "$query" | sed -n 's/^.*name=\([^&]*\).*$/\1/p' | sed "s/%20/ /g" } But I want to replace the "name" with the parameter that I pass ...
4
votes
2answers
245 views

Combine two commands in .bash_profile

In my .bash_profile file, I'd like to setup a single command alias that is two commands that execute one after another. The first command takes an argument from the command line and the second is ...
2
votes
2answers
709 views

creating simple command for sudo apt-get install?

I need to run these commands very often: sudo apt-get install <package> sudo apt-get remove <package> Can I make it simple like: install <package> remove <package> I ...
2
votes
3answers
318 views

Prefix every argument with -o in BASH

How do I prefix -p to every argument passed to my function? Modifying the arguments themselves and creating a new array are both fine.
-1
votes
3answers
384 views

calling functions within a function

I need to fetch the results of different time ranges and email the results, but i am having trouble with the email part of the script, how can i send an email with both results? (15min range and ...
4
votes
4answers
753 views

Is it possible to source a file in bash, but skipping specific functions?

Suppose I have bash_functions.sh: function test(){ } function test2(){ } And in my ~/.bashrc I do: source ~/bash_functions.sh Is it possible to, when sourcing it, avoid sourcing a specific ...
1
vote
3answers
2k views

alias or bash function does not work

When I create alias wd='ps -ef | grep java | awk {'print $2 " " $9'} | egrep "(A|B|C|D)"' or function wd () { ps -ef | grep java | awk '{print $2}' ... } in my .bashrc file, I get errors. ...
1
vote
4answers
2k views

how can i use sudo within a function?

i have written a function which acts in a similar way to tee but also pre-pends a datestamp. everything works fine except when i want to output to a file which is only root writeable (in my case a ...
4
votes
4answers
613 views

How to make functions created in a bash script persist like those in .bashrc?

My .bashrc was getting a little long, so I decided to break it up into smaller files according to topic and then call these files from within .bashrc as so #my long .bashrc file bash .topic1rc bash ...
3
votes
2answers
4k views

Passing a variable to a bash script when sourcing it in another bash script?

Suppose I have in main.sh: NAME="$HOME" if [ -f "$HOME/install.sh" ] then . "$HOME/install.sh" "$NAME" fi and in install.sh: echo $1 This is supposed to echo /home/user/, but it echoes ...
18
votes
1answer
1k views

Aliases vs functions vs scripts

This site says, "Shell functions are faster [than aliases]. Aliases are looked up after functions and thus resolving is slower. While aliases are easier to understand, shell functions are preferred ...