第3章 文件操作
fflush 函数:
int fflush(FILE *stream);
fseek
fgetc getc getchar
fputc putc putchar
fgets gets
printf fprintf sprintf (for file string) %g double %% output "%"
%-10s ,%*s following 5,"string"
scanf fscanf ssanf (the purpose of inserting a blank is for ingnoring blank characters)
%[]:读取一个字符集合
other functions:
fgetpos fsetpos ftell rewind freopen setvbuf remove
文件和目录的维护
chmod chown
unlink link symlink
mkdir rmdir
chdir getcwd
扫描目录
opendir closedir
readdir telldir seekdir
include <sys/types.h> .<dirent.h>
错误处理:
strerror perror
/proc文件系统:
/proc/cpuinfo meminfo version //cat to view
/proc/net/sockstat
/proc/sys/fs/file-max //edit max number of open file in same time : echo "80000" >/proc/sys/fs/file-max
高级管理:
fcntl:
fcntl(filedes,F_DUPFD,newfd)
fcntl(fd,F_GETFD)
fcntl(fd,F_SETFD,flags) //only for seting flag FD_CLOEXEC
mmap: 建立一段可以被两个或多个程序读写的内容
msync: synchronize mapping file
munmap: release memory