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How can I remove the first line of a text file using bash/sed script?
...you the last 5 lines of the input. The + sign kind of inverts the argument and make tail print anything but the first x-1 lines. tail -n +1 would print the whole file, tail -n +2 everything but the first line, etc.
GNU tail is much faster than sed. tail is also available on BSD and the -n +2 flag i...
What are best practices for validating email addresses on iOS 2.0
...his modification of DHValidation:
- (BOOL) validateEmail: (NSString *) candidate {
NSString *emailRegex =
@"(?:[a-z0-9!#$%\\&'*+/=?\\^_`{|}~-]+(?:\\.[a-z0-9!#$%\\&'*+/=?\\^_`{|}"
@"~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\"
@"x7f]|\\\\[\\x01-\\x09\\x0b\\x0c...
SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verify failed
...SL_CERT_FILE=/usr/local/etc/openssl/certs/cert.pem
– andersjanmyr
Dec 20 '12 at 12:04
5
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How to find the largest file in a directory and its subdirectories?
We're just starting a UNIX class and are learning a variety of Bash commands. Our assignment involves performing various commands on a directory that has a number of folders under it as well.
...
How do I change permissions for a folder and all of its subfolders and files in one step in Linux?
I would like to change permissions of a folder and all its sub folders and files in one step (command) in Linux.
16 Answers...
Can a local variable's memory be accessed outside its scope?
...u rent a hotel room. You put a book in the top drawer of the bedside table and go to sleep. You check out the next morning, but "forget" to give back your key. You steal the key!
A week later, you return to the hotel, do not check in, sneak into your old room with your stolen key, and look in the ...
How do I find the location of the executable in C? [duplicate]
...
To summarize:
On Unixes with /proc really straight and realiable way is to:
readlink("/proc/self/exe", buf, bufsize) (Linux)
readlink("/proc/curproc/file", buf, bufsize) (FreeBSD)
readlink("/proc/self/path/a.out", buf, bufsize) (Solaris)
On Unixes without /proc (i.e. if ab...
How do I find the location of my Python site-packages directory?
...
There are two types of site-packages directories, global and per user.
Global site-packages ("dist-packages") directories are listed in sys.path when you run:
python -m site
For a more concise list run getsitepackages from the site module in Python code:
python -c 'import sit...
How efficient is locking an unlocked mutex? What is the cost of a mutex?
...bunch of mutexes or a single one for an object.
If you have many threads and the access to the object happens often, then multiple locks would increase parallelism. At the cost of maintainability, since more locking means more debugging of the locking.
How efficient is it to lock a mutex? I.e....
Solutions for distributing HTML5 applications as desktop applications? [closed]
...by GitHub for building cross-platform desktop applications with HTML, CSS, and JavaScript. Electron accomplishes this by combining Chromium and Node.js into a single runtime and apps can be packaged for Mac, Windows, and Linux. (source)
The folks at github use this to provide their code editor Ato...