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What's the best way to check if a file exists in C?
...exists
} else {
// file doesn't exist
}
You can also use R_OK, W_OK, and X_OK in place of F_OK to check for read permission, write permission, and execute permission (respectively) rather than existence, and you can OR any of them together (i.e. check for both read and write permission using R...
Why does Android use Java? [closed]
...
Some points:
Java is a known language, developers know it and don't have to learn it
it's harder to shoot yourself with Java than with C/C++ code since it has no pointer arithmetic
it runs in a VM, so no need to recompile it for every phone out there and easy to secure
large number ...
Get last n lines of a file, similar to tail
I'm writing a log file viewer for a web application and for that I want to paginate through the lines of the log file. The items in the file are line based with the newest item on the bottom.
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What's the best way to send a signal to all members of a process group?
...se if the tree is the result of forking from a server start or a shell command line.) You can discover process groups using GNU ps as follows:
ps x -o "%p %r %y %x %c "
If it is a process group you want to kill, just use the kill(1) command but instead of giving it a process number, give it th...
Git for beginners: The definitive practical guide
...k, after seeing this post by PJ Hyett , I have decided to skip to the end and go with Git .
37 Answers
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How to move the cursor word by word in the OS X Terminal
...now the combination Ctrl + A to jump to the beginning of the current command, and Ctrl + E to jump to the end.
17 Answ...
What is an uninterruptible process?
Sometimes whenever I write a program in Linux and it crashes due to a bug of some sort, it will become an uninterruptible process and continue running forever until I restart my computer (even if I log out). My questions are:
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rsync error: failed to set times on “/foo/bar”: Operation not permitted
I'm getting a confusing error from rsync and the initial things I'm finding from web searches (as well as all the usual chmod'ing) are not solving it:
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How do I get bash completion to work with aliases?
..._git_complete g __git_main to get code completition working on all git commands.
– Ondrej Machulda
Apr 15 '13 at 12:03
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How to output only captured groups with sed?
...as well as specifying what you do want.
string='This is a sample 123 text and some 987 numbers'
echo "$string" | sed -rn 's/[^[:digit:]]*([[:digit:]]+)[^[:digit:]]+([[:digit:]]+)[^[:digit:]]*/\1 \2/p'
This says:
don't default to printing each line (-n)
exclude zero or more non-digits
include on...