... Unix^2.1

By Unix, the author means all the Unix derivatives (Linux, Solaris, BSD)

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... POSIX^2.2

POSIX is a operating system interface standard. Most unix-like systems aim for POSIX compliance.

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... building^3.1

Actually, make could be used to automate almost any task. However, it's used almost exclusively for program construction.

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... makefile^3.2

Any text after a # character is considered a comment and is ignored by Make

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... points^5.1

Extensive use of the GOTO statement, found in many languages, is largely considered poor programming practice. GOTO makes it extremely difficult to reason about the execution order and correctness of code.

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... segfaults^5.2

A segmentation violation is an error in which a program tried to access memory that has not been allocated to it

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... code^6.1

Donald Knuth asserts, ``In non-I/O-bound programs, less than four per cent of a program generally accounts for more than half of its running time.''

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... numbers^8.1

The reader will quickly see that $\sum_{i=1}^n = \frac{n (n+1)}{2}$, which can be calculated using only an integer addition, and integer mulitply, and a bitshift. This is a good example of how a little thought about the problem usually provides more benefit than clever programming techniques.

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... threads^8.2

Threads can be thought of as a lightweight process. They incur less operating system overhead and scheduling penalities than an process. A process may have many threads of control, determined by the operating system and/or system administrator

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... worker^8.3

The author suggests setting DEFAULT(NONE) so that variables are not automatically scoped private or shared.

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... path^8.4

The absolute path is the fully qualified name of the file. For example /usr/bin/ls rather than just ls or bin/ls.

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... network^8.5

Performance tip: if reading or writing temporary files during a calculation, don't use filesystem that is mounted over the network. use a local disk

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... hosts^8.6

Either DNS names or IP addresses

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... IEEE^A.1

Institute of Electrical and Electronics Engineers

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... Unix^A.2

Mac OSX includes the OpenSSH client ``ssh''

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... cryptography^A.3

Public key cryptography allows the encoding key to be revealed without weakening or compromising the security of the encoded message. OpenSSH uses the RSA system

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... password^A.4

However, most OpenSSH servers are configured to fall back to regular password authentication if other authentication methods fail.

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... integer^A.5

UID 0 is reserved for the system administrator and super-user, root

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...bash^A.6

Bash is the Borne Again SHell which is developed as part of the GNU project. Most Unix machines have a version of Bash available, even if it's not the default shell.

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... program^A.7

In the simplest model this means interpreting the contents of the file as instructions, but a complete treatment of program loading is beyond the scope of this document.

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... contents^A.8

The names of the files in the directory, not the contents of the files themselves.

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.....)^A.9

These are special directories. . always points to the directory that it's in, and .. always points to the current directories parent directory.

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... times^A.10

Under certain circumstances, programs close the standard file handles or replace them other files

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... Screen^A.11

C-a C-d

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... functions^A.12

Users can control where man searchs for manuals with the MANPATH environment variable.

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... variable^A.13

See A.3.3

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