Understanding Linux I/O Redirection: Combining stdout and stderr with >file 2>&1 &
The syntax command >file 2>&1 & is a common yet frequently misunderstood shell construct. It performs three distinct operations in one line: output redirection, error stream merging, and background execution.
File Descriptors and Stream Behavior
Every process in Linux starts with three default file descriptors:
0 (stdin): Input s ...
Posted on Mon, 13 Jul 2026 16:28:26 +0000 by usawh
Analyzing the Implementation of the select System Call
Understanding the select System Call
The select system call provides synchronous I/O multiplexing, allowing a program to monitor multiple file descriptors for readiness. This analysis explores its internal implementation in the Linux kernel.
User Interface
The select API is defined as follows:
#include <sys/select.h>
int select(int maxfd ...
Posted on Thu, 14 May 2026 13:42:45 +0000 by immot