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Chris Down
  • Member for 10 years, 8 months
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737 votes
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How can I resolve a hostname to an IP address in a Bash script?

725 votes
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Finding the PID of the process using a specific port?

454 votes
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Execute vs Read bit. How do directory permissions in Linux work?

265 votes
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How to rsync only new files

264 votes
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How do I determine the number of RAM slots in use?

237 votes
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How to check if a shell is login/interactive/batch

213 votes
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What does env x='() { :;}; command' bash do and why is it insecure?

197 votes
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In CentOS, what is the difference between yum update and yum upgrade?

196 votes

How to use wildcards (*) when copying with scp?

169 votes

watch command alias expansion

167 votes

Prepending a timestamp to each line of output from a command

164 votes

Why is "echo" so much faster than "touch"?

156 votes
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What is the difference between "sort -u" and "sort | uniq"?

138 votes
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Day of week {0-7} in crontab has 8 options, but we have only 7 days in a week

137 votes
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What does the "@" (at) symbol mean on OSX ls?

135 votes
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How do I check if a variable exists in an 'if' statement?

133 votes
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Make cd follow symbolic links

126 votes
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How to run a command that involves redirecting or piping with sudo?

120 votes

Find duplicate files

112 votes
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How to enable reverse search in zsh?

90 votes

Can't use exclamation mark (!) in bash?

90 votes
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How do I list all installed programs?

89 votes
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In Bash scripting, what's the meaning of " $! "?

80 votes
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What do the bash-builtins 'set' and 'export' do?

80 votes
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What does the 'd' mean in ls -al results and what is that slot called?

73 votes
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How does the Linux kernel update itself?

69 votes
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Using sed to get rid of characters < > ,

64 votes

How can I delete all lines in a file using vi?

61 votes
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How can I access a directory outside a chroot from within it?

60 votes
Accepted

In zsh how can I list all the environment variables?

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