April 2025
Intermediate to advanced
248 pages
6h 19m
Portuguese (Portugal, Brazil)
Content preview from Linux eficiente na linha de comandosBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
... ficheiros correspondentes
Este brash-one liner é inspirado numa utilização real do Mediawiki, o software que alimenta a Wikipedia e milhares de outras wikis. O Mediawiki permite que os utilizadores carreguem imagens para visualização. A maioria dos utilizadores segue um processo manual através de formulários web: clica em Escolher ficheiro para abrir uma caixa de diálogo de ficheiros, navega até um ficheiro de imagem e seleciona-o, adiciona um comentário descritivo no formulário e clica em Carregar. Os administradores da wiki utilizam um método mais automatizado: um script que lê um diretório inteiro e carrega as suas imagens. Cada ficheiro de imagem (digamos, bald_eagle.jpg) é emparelhado com um ficheiro de texto(bald_eagle.txt) contendo um comentário descritivo sobre a imagem.
Imagina que estás perante um enorme diretório que contém apenas ficheiros JPEG e TXT. Queres confirmar que cada ficheiro de imagem tem um ficheiro de texto correspondente e vice-versa. Aqui tens uma versão mais pequena desse diretório:
$ ls bald_eagle.jpg blue_jay.jpg cardinal.txt robin.jpg wren.jpg bald_eagle.txt cardinal.jpg oriole.txt robin.txt wren.txt
Vamos desenvolver duas soluções diferentes para identificar quaisquer ficheiros não correspondentes. Para a primeira solução, cria duas listas, uma para os ficheiros JPEG e outra para os ficheiros de texto, e utiliza cut para retirar as extensões de ficheiro .txt e .jpg:
$ ls *.jpg | cut -d. -f1 bald_eagle blue_jay cardinal robin wren $ ls *.txt | cut -d. -f1 ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.