Standard I/O Library Overview

SET

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off_t

<p>fgetpos</p> Signup and view all the answers

<p>printf</p> Signup and view all the answers

<p>descriptor</p> Signup and view all the answers

<p>binary</p> Signup and view all the answers

<p>POSIX</p> Signup and view all the answers

<p>write</p> Signup and view all the answers

<p>append</p> Signup and view all the answers

<p>truncate</p> Signup and view all the answers

<p>correctly</p> Signup and view all the answers

<p>restrictions</p> Signup and view all the answers

<p>pathname</p> Signup and view all the answers

<p>wb+</p> Signup and view all the answers

<p>limits.h</p> Signup and view all the answers

<p>static</p> Signup and view all the answers

<p>obsolescent</p> Signup and view all the answers

<p>terminal</p> Signup and view all the answers

<p>unbuffered</p> Signup and view all the answers

<p>unbuffered</p> Signup and view all the answers

<p>newline</p> Signup and view all the answers

<p>terminal</p> Signup and view all the answers

<p>interactive</p> Signup and view all the answers

<p>fixed</p> Signup and view all the answers

<p>unbuffered</p> Signup and view all the answers

<p>scanf</p> Signup and view all the answers

<p>conversion specification</p> Signup and view all the answers

<p>unread</p> Signup and view all the answers

<p>conversion</p> Signup and view all the answers

<p>fldwidth</p> Signup and view all the answers

<p>conversion</p> Signup and view all the answers

<p>4294967295</p> Signup and view all the answers

<p>convtype</p> Signup and view all the answers

<p>fclose</p> Signup and view all the answers

<p>stream</p> Signup and view all the answers

<p>BSZ</p> Signup and view all the answers

<p>printf</p> Signup and view all the answers

<p>fflush</p> Signup and view all the answers

<p>fseek</p> Signup and view all the answers

<p>fflush</p> Signup and view all the answers

<p>Linux</p> Signup and view all the answers

<p>fclose</p> Signup and view all the answers

<p>12</p> Signup and view all the answers

<p>thread</p> Signup and view all the answers

<p>ID</p> Signup and view all the answers

<p>integers</p> Signup and view all the answers

<p>process</p> Signup and view all the answers

<p>Library</p> Signup and view all the answers

<p>address</p> Signup and view all the answers

<p>meaningful</p> Signup and view all the answers

<p>management</p> Signup and view all the answers

<p>structure</p> Signup and view all the answers

<p>foo</p> Signup and view all the answers

<p>reference</p> Signup and view all the answers

<p>reference</p> Signup and view all the answers

<p>PTHREAD_MUTEX_INITIALIZER</p> Signup and view all the answers

<p>f_lock</p> Signup and view all the answers

<p>HASH</p> Signup and view all the answers

<p>NULL</p> Signup and view all the answers

<p>parallelism</p> Signup and view all the answers

<p>write</p> Signup and view all the answers

<p>write</p> Signup and view all the answers

<p>modified</p> Signup and view all the answers

<p>read</p> Signup and view all the answers

<p>writers</p> Signup and view all the answers

<p>deadlock</p> Signup and view all the answers

<p>pthread_mutex_timedlock</p> Signup and view all the answers

<p>0</p> Signup and view all the answers

<p>errors</p> Signup and view all the answers

<p>0</p> Signup and view all the answers

<p>point</p> Signup and view all the answers

<p>EBUSY</p> Signup and view all the answers

<p>pthread_join</p> Signup and view all the answers

<p>release</p> Signup and view all the answers

<p>initialize</p> Signup and view all the answers

<p>deadlock</p> Signup and view all the answers

<p>shared</p> Signup and view all the answers

<p>destroy</p> Signup and view all the answers

<p>lock</p> Signup and view all the answers

<p>count</p> Signup and view all the answers

<p>done</p> Signup and view all the answers

<p>arbitrary</p> Signup and view all the answers

<p>attr</p> Signup and view all the answers

<p>signal</p> Signup and view all the answers

<p>mutex</p> Signup and view all the answers

<p>mutex</p> Signup and view all the answers

<p>condition</p> Signup and view all the answers

<p>call</p> Signup and view all the answers

<p>while</p> Signup and view all the answers

<p>mutex</p> Signup and view all the answers

<p>m_next</p> Signup and view all the answers

Output is collected in a buffer until a newline character is encountered, then written to the destination.

Buffer size is fixed: Output may happen before newline if filled. All line-buffered output flushes when unbuffered input is requested.

Characters are output immediately without buffering.

Output is always unbuffered for quick error messages.

Output is collected in a buffer until the buffer is full, or a specific instruction to write is made.

Streams connected to terminals or input/output devices where prompt responses are expected.

Buffered if not interactive, otherwise line buffered. If interactive, they are line-buffered.

The set of functions used for input and output operations (such as fputc, fputs, write).

Positioning text files might not be straightforward byte offsets, especially on non-UNIX systems.

Functions for positioning files using off_t type for offsets.

Specifies that the file position should be relative to the file's beginning.

Functions for saving and restoring file positions using fpos_t.

printf functions handle formatted output operations.

Associates a file descriptor with a standard I/O stream.

Standard C function for opening files.

Writing to the end of a file.

Opens a file to allow appending without truncating.

An integer representing an open file in the OS.

A file that contains raw data.

Used to seek to a specific position within a file.

File access allowing both reading and writing capabilities.

Generates a unique pathname that doesn't exist.

A pointer to a statically allocated pathname string.

A pointer to the pathname stored in the user-provided array

Creates a temporary binary file automatically deleted on closing/termination.

Maximum number of times tmpnam can generate unique temporary files

Functions used to parse input strings and convert character sequences into variables.

Number of input items successfully assigned, or EOF for input errors or end of file before conversion.

Instructions on how to convert input into variables.

The percent sign (%) indicates the start of a conversion specification.

Optional asterisk (*) before conversion type in format to suppress storing the result in a variable.

Maximum field width in characters for input conversion.

Specifies the size of the argument variable for conversions (like printf functions).

Specifies the type of variable to convert input into (e.g., integer, float).

A null byte (\0) is appended to the buffer of a memory stream when actions like fclose, fflush, fseek, fseeko, or fsetpos are called.

Flushing a memory stream forces writing the data in the stream's buffer to the underlying memory.

fclose function closes the stream and it appends a null byte.

A stream that utilizes a user-provided buffer instead of a traditional file.

A temporary location in memory to store data read from or written to a stream.

Memory streams append null bytes after handling operations, like fflush or fseek.

fflush function writes buffer contents to underlying memory, and appends a null after.

Activities that change the read/write position in a stream buffer.

On Solaris, thread IDs are represented as simple integers starting from 1.

FreeBSD uses pointers to the thread data structure as thread IDs.

Mac OS X employs a mixture of approaches for its thread IDs, using different address ranges for the main thread vs. created threads.

Linux 2.4 used separate processes for each thread, making it challenging to align with traditional POSIX threads.

Linux 2.6 introduced NPTL, a native POSIX thread implementation, improving thread management.

A thread implementation for the Linux kernel, introduced in version 2.6, that aligns more closely with POSIX thread standards.

Linux 2.6's NPTL utilizes unsigned long integers for thread IDs, appearing like pointers.

Thread IDs on Linux 2.6 are unsigned long integers, even though they appear similar to pointers.

The initial design used separate locks for the structure reference count and other parts of the structure, leading to potential race conditions if a thread blocks while holding the structure mutex.

The improved approach uses a single hash list lock to protect both the structure reference count and the linked list of structures. The structure mutex is then used to protect the rest of the structure's contents.

The hash lock protects the reference count and the linked list of 'foo' structures, ensuring thread-safe access to the reference count and the linked list.

The structure mutex is separate to protect the remaining data within the foo structure from concurrent access by other threads. It ensures that operations on the structure's data remain atomic and consistent.

The f_count variable acts as a reference counter, tracking how many threads are currently using the structure. It ensures that the structure is not freed prematurely while still being referenced.

Each 'foo' structure is added to the hash list by setting its f_next pointer to the current head of the list at the corresponding hash index, and then updating the fh[idx] pointer to point to the new structure.

The pthread_mutex_init function initializes the mutex associated with each 'foo' structure, ensuring safe and thread-safe access to the structure's data.

Acquiring the f_lock mutex after the hash lock maintains a lock ordering that prevents deadlocks. This ensures that threads holding the hash lock cannot be blocked while waiting for a nested f_lock.

Acquires a reader--writer lock in shared mode. Multiple readers can acquire the lock simultaneously. Returns 0 if successful, an error number otherwise.

Acquires a reader--writer lock in exclusive mode. Only one writer can hold the lock at a time. All readers are blocked until the lock is released. Returns 0 if successful, an error number otherwise.

Releases a reader--writer lock previously acquired by either pthread_rwlock_rdlock or pthread_rwlock_wrlock. Returns 0 if successful, an error number otherwise.

Attempts to acquire a reader--writer lock in shared mode. If the lock is already held by a writer, it returns an error immediately. Otherwise, it acquires the lock and returns 0.

Attempts to acquire a reader--writer lock in exclusive mode. If the lock is already held, it returns an error immediately. Otherwise, it acquires the lock and returns 0.

A synchronization primitive that allows multiple threads to read shared data concurrently, but only one thread at a time to write data. It's a more efficient locking mechanism than mutexes when multiple readers are common.

Reader--writer locks offer performance advantages over mutexes in scenarios with frequent reading and infrequent writing. They allow concurrent reading, increasing efficiency, while still ensuring data consistency during writes.

A mechanism that prevents multiple threads from accessing a shared resource simultaneously. A thread must acquire the lock before accessing the resource and release it afterward, ensuring exclusive access.

A situation where two or more threads are blocked indefinitely, each waiting for a resource held by another thread. This can occur when a thread attempts to acquire a lock it already owns, leading to a circular dependency.

A function that attempts to acquire a mutex lock with a specified timeout. If the lock is not available within the given time, the function returns an error.

A state of a reader-writer lock where only one thread can access the shared resource. This state ensures exclusive access for modification.

A state of a reader-writer lock where multiple threads can read the shared resource simultaneously, but no thread can write to it. This state allows for efficient read operations.

A situation where a thread is repeatedly denied access to a resource because other threads continuously acquire it. In the context of reader-writer locks, it can occur when a constant stream of readers prevents a waiting writer from acquiring the write lock.

Reader-writer locks are suitable for situations where a shared resource is read more frequently than it's modified. They offer a performance advantage in such cases.

A mechanism used for thread synchronization. It allows a thread to wait until a specific condition becomes true.

A function that signals (wakes up) one thread waiting on a condition variable. This is useful when a condition has become true and another thread should be allowed to proceed.

A function that signals (wakes up) all threads waiting on a condition variable. Used when multiple threads are waiting and the condition is true for all of them.

A mechanism used to protect shared resources. Only one thread can hold the mutex at a time, ensuring that only one thread accesses the resource.

A function that puts a thread to sleep until it is signaled by another thread. This function must be called within a mutex lock, and it automatically releases the mutex before waiting.

The process of coordinating the execution of multiple threads so they access shared resources correctly and avoid conflicts.

Condition variables are used in conjunction with mutexes. They allow threads to wait for a specific condition to become true and then be signaled to proceed.

Checking the condition within a while loop ensures that a thread that wakes up prematurely (before the condition is truly met) will check again and continue waiting if necessary.

A synchronization mechanism that allows multiple threads to wait until all threads reach a specific point before continuing execution.

A function used to initialize a barrier object. It specifies the number of threads that need to reach the barrier before threads can continue.

A function used to deinitialize a barrier object. It releases any resources allocated for the barrier.

A function used by a thread to indicate that it has completed its work and is ready to wait at the barrier for other threads.

The number of threads that must reach the barrier before all threads are allowed to continue execution.

Optional attributes to be used when setting up a barrier object.

Allows threads to coordinate their actions, ensuring they all reach a specific point in their execution before proceeding.

Any technique for coordinating and managing the behavior of concurrent processes or threads to ensure correct interaction.