Linux dup() and dup2() System Calls Linux open() System Call 常见问题及解决方法 文件描述符泄漏:如果忘记关闭复制的文件描述符,可能会导致文件描述符泄漏。确保在使用完文件描述符后调用 close() 函数关闭它们。 权限问题:在尝试打开或复制文件描述符时,可能会遇到权限不足的问题。检查文件权限
oldfd, then dup2() does nothing, and returns newfd. After a successful return from one of these system calls, the old and new file descriptors may be used interchangeably. They refer to the same open file description (see open(2)) and thus share file offset and file status flags; for...
2,复制文件描述符(dup、dup2、fcntl) 一,文件共享 1,一个进程打开两个文件内核数据结构 说明: 文件描述符表:每个进程都有一张,彼此独立,每个文件描述符表项都指向一个文件表,文件描述符0(STDIN_FILENO)、1(STDOUT_FILENO)、2(STDERR_FILENO),默认已经打开,分别表示:标准输入,标准输出,标准错误设备。
dup2is asystem callsimilar todupin that it duplicates one file descriptor, making them aliases, and then deleting the old file descriptor. This becomes very useful when attempting to redirect output, as it automatically takes care of closing the new file descriptor, performing the redirection in ...
On success, these system calls return the new descriptor. On error, -1 is returned, and errno is set appropriately. 示例:一句话打印两次,先打入文件,后打至屏幕 代码语言:javascript 代码运行次数:0 运行 AI代码解释 /*** >File Name : dup_test.c >Author : QQ >Company : QQ >Create Time: ...
dup, dup2, dup3- duplicate afiledescriptor SYNOPSIS #include<unistd.h>intdup(intoldfd);intdup2(intoldfd,intnewfd);#define_GNU_SOURCE#include<unistd.h>intdup3(intoldfd,intnewfd,intflags); DESCRIPTION These system calls create a copy of thefiledescriptor oldfd. ...
In Unix-like operating systems, dup and dup2 system calls create a copy of a given file descriptor. This new descriptor actually does not behave like a copy, but like an alias of the old one. 以上来源于:Wikipedia 学习怎么用 权威例句 ...
Unix System Call: dup Function - Learn about the dup function in Unix system calls, its usage, parameters, and examples to duplicate file descriptors efficiently.
int dup2(Old,New)intOld,New; int dup(FileDescriptor)intFileDescriptor; Description Thefcntlsubroutine performs controlling operations on the open file specified by theFileDescriptorparameter. If Network File System (NFS) is installed on your system, the open file can reside on another node. Thefcntl...
and returns newfd. 函数参数 oldfd:旧的文件描述符 newfd:新的文件描述符 函数返回值 On success, these system callsreturn thenew descriptor. On error -1 is returned, errno is appropriately. 示例:一句话打印两次,先打入文件,后打至屏幕 /*** >File Name : dup_test.c >Author :...