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Commands by frans

Commands by frans from sorted by
Terminal - Commands by frans - 9 results
touch -d $(zenity --calendar --date-format=%F) filename
2011-11-18 17:58:47
User: frans
Functions: touch
Tags: touch zenity timestamp interactive
10
Up
Down
Change/Modify timestamp interactively
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
date -ud "1970/01/01 00:29:36" +%s
2011-11-01 17:02:46
User: frans
Functions: date
Tags: echo date time
-4
Up
Down
Convert HH:MM:SS into seconds

uses the -u switch for UTC

Another way could be

echo $(($(date -ud "00:29:36" +%s)%86400))
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
param=${param:-$(read -p "Enter parameter: "; echo "$REPLY")}
2011-09-08 20:48:31
User: frans
Functions: echo read
Tags: script bash tricks parameter parameter expansion interactive
7
Up
Down
Enter parameter if empty (script becomes interactive when parameters are missing)

Can be used for command line parameters too.

If you have a more complicated way of entering values (validation, GUI, ...), then write a function i.e. EnterValue() that echoes the value and then you can write:

param=${param:-$(EnterValue)}
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
read day month year < <(date +'%d %m %y')
2011-07-30 06:06:29
User: frans
Functions: date read
Tags: bash read
10
Up
Down
Multiple variable assignments from command output in BASH

No command substitution but subshell redirection

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
F=index.html; for i in *; do [[ $i = $F ]] && continue; echo "<li><a href='$i'>$i</a>"; done >$F
2011-05-08 20:57:24
User: frans
Functions: echo
Tags: bash
0
Up
Down
Create cheap and easy index.html file

Just to avoid link to itself

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
Confirm() { read -sn 1 -p "$1 [Y/N]? "; [[ $REPLY = [Yy] ]]; }
2010-11-22 11:01:14
User: frans
Functions: read
Tags: read
11
Up
Down
Ask user to confirm

Returns true if user presses the key.

Use it like

Confirm "Continue" && do action
Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
Split() { eval "$1=( \"$(echo "${!1}" | sed "s/$2/\" \"/g")\" )"; }
2010-02-08 17:41:59
User: frans
Functions: eval
1
Up
Down
Function to split a string into an array

It works as a method applicated to a variable, converts the string variable into an array

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
atrm $(atq|cut -f1)
2010-01-20 08:04:35
User: frans
Functions: atrm cut
Tags: at
0
Up
Down
remove at jobs

Removes all the at shedules jobs

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
pidof -x -o $$ ${0##*/} && exit
2009-11-20 12:58:41
User: frans
Functions: pidof
8
Up
Down
exit if another instance is running
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate