本文总阅读量 本站访客数人次 本站总访问量
gongluck's blog
C/C++ Golang 音视频流媒体
分布式存储专题

八、分布式存储专题

0.项目仓库

1.FastDFS

FastDFS架构

1.1 编译安装

# 下载
wget https://github.com/happyfish100/libfastcommon/archive/V1.0.43.tar.gz
# 解压
sudo tar -xzvf V1.0.43.tar.gz libfastcommon-1.0.43
# 进入解压后的目录
cd libfastcommon-1.0.43
# 编译代码
sudo ./make.sh
# 安装
sudo ./make.sh install
#export LD_LIBRARY_PATH=/usr/lib64/:$LD_LIBRARY_PATH
sudo ln -s /usr/lib64/libfastcommon.so /usr/lib/libfastcommon.so

# 下载
wget https://github.com/happyfish100/fastdfs/archive/V6.06.tar.gz
# 解压
sudo tar -zxvf V6.06.tar.gz fastdfs-6.06
# 进入解压后的目录
cd fastdfs-6.06
# 编译代码
sudo ./make.sh
# 安装
sudo ./make.sh install

1.2 tracker.conf

# is this config file disabled
# false for enabled
# true for disabled
disabled = false

# bind an address of this host
# empty for bind all addresses of this host
bind_addr = 172.28.123.249  #tracker 所在服务器的 ip

# the tracker server port
port = 22122    #服务器端口

# connect timeout in seconds
# default value is 30
# Note: in the intranet network (LAN), 2 seconds is enough.
connect_timeout = 5

# network timeout in seconds for send and recv
# default value is 30
network_timeout = 60

# the base path to store data and log files
base_path = /mnt/e/ubuntu/tracker    #表示tracker日志存放的路径,此路径必须已经存在

# max concurrent connections this server support
# you should set this parameter larger, eg. 10240
# default value is 256
max_connections = 1024

# accept thread count
# default value is 1 which is recommended
# since V4.07
accept_threads = 1

# work thread count
# work threads to deal network io
# default value is 4
# since V2.00
work_threads = 4

# the min network buff size
# default value 8KB
min_buff_size = 8KB

# the max network buff size
# default value 128KB
max_buff_size = 128KB

# the method for selecting group to upload files
# 0: round robin
# 1: specify group
# 2: load balance, select the max free space group to upload file
store_lookup = 2

# which group to upload file
# when store_lookup set to 1, must set store_group to the group name
store_group = group2

# which storage server to upload file
# 0: round robin (default)
# 1: the first server order by ip address
# 2: the first server order by priority (the minimal)
# Note: if use_trunk_file set to true, must set store_server to 1 or 2
store_server = 0

# which path (means disk or mount point) of the storage server to upload file
# 0: round robin
# 2: load balance, select the max free space path to upload file
store_path = 0

# which storage server to download file
# 0: round robin (default)
# 1: the source storage server which the current file uploaded to
download_server = 0

# reserved storage space for system or other applications.
# if the free(available) space of any stoarge server in 
# a group <= reserved_storage_space, no file can be uploaded to this group.
# bytes unit can be one of follows:
### G or g for gigabyte(GB)
### M or m for megabyte(MB)
### K or k for kilobyte(KB)
### no unit for byte(B)
### XX.XX% as ratio such as: reserved_storage_space = 10%
reserved_storage_space = 20%

#standard log level as syslog, case insensitive, value list:
### emerg for emergency
### alert
### crit for critical
### error
### warn for warning
### notice
### info
### debug
log_level = info

#unix group name to run this program, 
#not set (empty) means run by the group of current user
run_by_group=

#unix username to run this program,
#not set (empty) means run by current user
run_by_user =

# allow_hosts can ocur more than once, host can be hostname or ip address,
# "*" (only one asterisk) means match all ip addresses
# we can use CIDR ips like 192.168.5.64/26
# and also use range like these: 10.0.1.[0-254] and host[01-08,20-25].domain.com
# for example:
# allow_hosts=10.0.1.[1-15,20]
# allow_hosts=host[01-08,20-25].domain.com
# allow_hosts=192.168.5.64/26
allow_hosts = *

# sync log buff to disk every interval seconds
# default value is 10 seconds
sync_log_buff_interval = 1

# check storage server alive interval seconds
check_active_interval = 120

# thread stack size, should >= 64KB
# default value is 256KB
thread_stack_size = 256KB

# auto adjust when the ip address of the storage server changed
# default value is true
storage_ip_changed_auto_adjust = true

# storage sync file max delay seconds
# default value is 86400 seconds (one day)
# since V2.00
storage_sync_file_max_delay = 86400

# the max time of storage sync a file
# default value is 300 seconds
# since V2.00
storage_sync_file_max_time = 300

# if use a trunk file to store several small files
# default value is false
# since V3.00
use_trunk_file = false 

# the min slot size, should <= 4KB
# default value is 256 bytes
# since V3.00
slot_min_size = 256

# the max slot size, should > slot_min_size
# store the upload file to trunk file when it's size <=  this value
# default value is 16MB
# since V3.00
slot_max_size = 1MB

# the alignment size to allocate the trunk space
# default value is 0 (never align)
# since V6.05
# NOTE: the larger the alignment size, the less likely of disk
#       fragmentation, but the more space is wasted.
trunk_alloc_alignment_size = 256

# if merge contiguous free spaces of trunk file
# default value is false
# since V6.05
trunk_free_space_merge = true

# if delete / reclaim the unused trunk files
# default value is false
# since V6.05
delete_unused_trunk_files = false

# the trunk file size, should >= 4MB
# default value is 64MB
# since V3.00
trunk_file_size = 64MB

# if create trunk file advancely
# default value is false
# since V3.06
trunk_create_file_advance = false

# the time base to create trunk file
# the time format: HH:MM
# default value is 02:00
# since V3.06
trunk_create_file_time_base = 02:00

# the interval of create trunk file, unit: second
# default value is 38400 (one day)
# since V3.06
trunk_create_file_interval = 86400

# the threshold to create trunk file
# when the free trunk file size less than the threshold,
# will create he trunk files
# default value is 0
# since V3.06
trunk_create_file_space_threshold = 20G

# if check trunk space occupying when loading trunk free spaces
# the occupied spaces will be ignored
# default value is false
# since V3.09
# NOTICE: set this parameter to true will slow the loading of trunk spaces 
# when startup. you should set this parameter to true when neccessary.
trunk_init_check_occupying = false

# if ignore storage_trunk.dat, reload from trunk binlog
# default value is false
# since V3.10
# set to true once for version upgrade when your version less than V3.10
trunk_init_reload_from_binlog = false

# the min interval for compressing the trunk binlog file
# unit: second, 0 means never compress
# FastDFS compress the trunk binlog when trunk init and trunk destroy
# recommand to set this parameter to 86400 (one day)
# default value is 0
# since V5.01
trunk_compress_binlog_min_interval = 86400

# the interval for compressing the trunk binlog file
# unit: second, 0 means never compress
# recommand to set this parameter to 86400 (one day)
# default value is 0
# since V6.05
trunk_compress_binlog_interval = 86400

# compress the trunk binlog time base, time format: Hour:Minute
# Hour from 0 to 23, Minute from 0 to 59
# default value is 03:00
# since V6.05
trunk_compress_binlog_time_base = 03:00

# max backups for the trunk binlog file
# default value is 0 (never backup)
# since V6.05
trunk_binlog_max_backups = 7

# if use storage server ID instead of IP address
# if you want to use dual IPs for storage server, you MUST set
# this parameter to true, and configure the dual IPs in the file
# configured by following item "storage_ids_filename", such as storage_ids.conf
# default value is false
# since V4.00
use_storage_id = false

# specify storage ids filename, can use relative or absolute path
# this parameter is valid only when use_storage_id set to true
# since V4.00
storage_ids_filename = storage_ids.conf

# id type of the storage server in the filename, values are:
## ip: the ip address of the storage server
## id: the server id of the storage server
# this paramter is valid only when use_storage_id set to true
# default value is ip
# since V4.03
id_type_in_filename = id

# if store slave file use symbol link
# default value is false
# since V4.01
store_slave_file_use_link = false

# if rotate the error log every day
# default value is false
# since V4.02
rotate_error_log = false

# rotate error log time base, time format: Hour:Minute
# Hour from 0 to 23, Minute from 0 to 59
# default value is 00:00
# since V4.02
error_log_rotate_time = 00:00

# if compress the old error log by gzip
# default value is false
# since V6.04
compress_old_error_log = false

# compress the error log days before
# default value is 1
# since V6.04
compress_error_log_days_before = 7

# rotate error log when the log file exceeds this size
# 0 means never rotates log file by log file size
# default value is 0
# since V4.02
rotate_error_log_size = 0

# keep days of the log files
# 0 means do not delete old log files
# default value is 0
log_file_keep_days = 0

# if use connection pool
# default value is false
# since V4.05
use_connection_pool = true

# connections whose the idle time exceeds this time will be closed
# unit: second
# default value is 3600
# since V4.05
connection_pool_max_idle_time = 3600

# HTTP port on this tracker server
http.server_port = 8080

# check storage HTTP server alive interval seconds
# <= 0 for never check
# default value is 30
http.check_alive_interval = 30

# check storage HTTP server alive type, values are:
#   tcp : connect to the storge server with HTTP port only, 
#        do not request and get response
#   http: storage check alive url must return http status 200
# default value is tcp
http.check_alive_type = tcp

# check storage HTTP server alive uri/url
# NOTE: storage embed HTTP server support uri: /status.html
http.check_alive_uri = /status.html

1.3 storage.conf

# is this config file disabled
# false for enabled
# true for disabled
disabled = false

# the name of the group this storage server belongs to
#
# comment or remove this item for fetching from tracker server,
# in this case, use_storage_id must set to true in tracker.conf,
# and storage_ids.conf must be configured correctly.
group_name = group1 #组,默认设置即可

# bind an address of this host
# empty for bind all addresses of this host
bind_addr = 172.28.123.249  #storage 所在服务器 ip

# if bind an address of this host when connect to other servers 
# (this storage server as a client)
# true for binding the address configured by the above parameter: "bind_addr"
# false for binding any address of this host
client_bind = true

# the storage server port
port = 23000    #服务器端口,默认设置即可

# connect timeout in seconds
# default value is 30
# Note: in the intranet network (LAN), 2 seconds is enough.
connect_timeout = 5

# network timeout in seconds for send and recv
# default value is 30
network_timeout = 60

# the heart beat interval in seconds
# the storage server send heartbeat to tracker server periodically
# default value is 30
heart_beat_interval = 30

# disk usage report interval in seconds
# the storage server send disk usage report to tracker server periodically
# default value is 300
stat_report_interval = 60

# the base path to store data and log files
# NOTE: the binlog files maybe are large, make sure
#       the base path has enough disk space,
#       eg. the disk free space should > 50GB
base_path = /mnt/e/ubuntu/storage    #用于storage存放日志,此目录必须存在

# max concurrent connections the server supported,
# you should set this parameter larger, eg. 10240
# default value is 256
max_connections = 1024

# the buff size to recv / send data from/to network
# this parameter must more than 8KB
# 256KB or 512KB is recommended
# default value is 64KB
# since V2.00
buff_size = 256KB

# accept thread count
# default value is 1 which is recommended
# since V4.07
accept_threads = 1

# work thread count
# work threads to deal network io
# default value is 4
# since V2.00
work_threads = 4

# if disk read / write separated
##  false for mixed read and write
##  true for separated read and write
# default value is true
# since V2.00
disk_rw_separated = true

# disk reader thread count per store path
# for mixed read / write, this parameter can be 0
# default value is 1
# since V2.00
disk_reader_threads = 1

# disk writer thread count per store path
# for mixed read / write, this parameter can be 0
# default value is 1
# since V2.00
disk_writer_threads = 1

# when no entry to sync, try read binlog again after X milliseconds
# must > 0, default value is 200ms
sync_wait_msec = 50

# after sync a file, usleep milliseconds
# 0 for sync successively (never call usleep)
sync_interval = 0

# storage sync start time of a day, time format: Hour:Minute
# Hour from 0 to 23, Minute from 0 to 59
sync_start_time = 00:00

# storage sync end time of a day, time format: Hour:Minute
# Hour from 0 to 23, Minute from 0 to 59
sync_end_time = 23:59

# write to the mark file after sync N files
# default value is 500
write_mark_file_freq = 500

# disk recovery thread count
# default value is 1
# since V6.04
disk_recovery_threads = 3

# store path (disk or mount point) count, default value is 1
store_path_count = 1

# store_path#, based on 0, to configure the store paths to store files
# if store_path0 not exists, it's value is base_path (NOT recommended)
# the paths must be exist.
#
# IMPORTANT NOTE:
#       the store paths' order is very important, don't mess up!!!
#       the base_path should be independent (different) of the store paths

store_path0 = /mnt/e/ubuntu/storage/fastdfs0  #真正存储数据的路径,此路径必须存在
#store_path1 = /home/yuqing/fastdfs2

# subdir_count  * subdir_count directories will be auto created under each 
# store_path (disk), value can be 1 to 256, default value is 256
subdir_count_per_path = 256

# tracker_server can ocur more than once for multi tracker servers.
# the value format of tracker_server is "HOST:PORT",
#   the HOST can be hostname or ip address,
#   and the HOST can be dual IPs or hostnames seperated by comma,
#   the dual IPS must be an inner (intranet) IP and an outer (extranet) IP,
#   or two different types of inner (intranet) IPs.
#   for example: 192.168.2.100,122.244.141.46:22122
#   another eg.: 192.168.1.10,172.17.4.21:22122

tracker_server = 172.28.123.249:22122  #指定 tracker 服务器地址和端口。不能是 127.0.0.1
#tracker_server = 192.168.209.122:22122

#standard log level as syslog, case insensitive, value list:
### emerg for emergency
### alert
### crit for critical
### error
### warn for warning
### notice
### info
### debug
log_level = info

#unix group name to run this program, 
#not set (empty) means run by the group of current user
run_by_group =

#unix username to run this program,
#not set (empty) means run by current user
run_by_user =

# allow_hosts can ocur more than once, host can be hostname or ip address,
# "*" (only one asterisk) means match all ip addresses
# we can use CIDR ips like 192.168.5.64/26
# and also use range like these: 10.0.1.[0-254] and host[01-08,20-25].domain.com
# for example:
# allow_hosts=10.0.1.[1-15,20]
# allow_hosts=host[01-08,20-25].domain.com
# allow_hosts=192.168.5.64/26
allow_hosts = *

# the mode of the files distributed to the data path
# 0: round robin(default)
# 1: random, distributted by hash code
file_distribute_path_mode = 0

# valid when file_distribute_to_path is set to 0 (round robin).
# when the written file count reaches this number, then rotate to next path.
# rotate to the first path (00/00) after the last path (such as FF/FF).
# default value is 100
file_distribute_rotate_count = 100

# call fsync to disk when write big file
# 0: never call fsync
# other: call fsync when written bytes >= this bytes
# default value is 0 (never call fsync)
fsync_after_written_bytes = 0

# sync log buff to disk every interval seconds
# must > 0, default value is 10 seconds
sync_log_buff_interval = 1

# sync binlog buff / cache to disk every interval seconds
# default value is 60 seconds
sync_binlog_buff_interval = 1

# sync storage stat info to disk every interval seconds
# default value is 300 seconds
sync_stat_file_interval = 300

# thread stack size, should >= 512KB
# default value is 512KB
thread_stack_size = 512KB

# the priority as a source server for uploading file.
# the lower this value, the higher its uploading priority.
# default value is 10
upload_priority = 10

# the NIC alias prefix, such as eth in Linux, you can see it by ifconfig -a
# multi aliases split by comma. empty value means auto set by OS type
# default values is empty
if_alias_prefix =

# if check file duplicate, when set to true, use FastDHT to store file indexes
# 1 or yes: need check
# 0 or no: do not check
# default value is 0
check_file_duplicate = 0

# file signature method for check file duplicate
## hash: four 32 bits hash code
## md5: MD5 signature
# default value is hash
# since V4.01
file_signature_method = hash

# namespace for storing file indexes (key-value pairs)
# this item must be set when check_file_duplicate is true / on
key_namespace = FastDFS

# set keep_alive to 1 to enable persistent connection with FastDHT servers
# default value is 0 (short connection)
keep_alive = 0

# you can use "#include filename" (not include double quotes) directive to 
# load FastDHT server list, when the filename is a relative path such as 
# pure filename, the base path is the base path of current/this config file.
# must set FastDHT server list when check_file_duplicate is true / on
# please see INSTALL of FastDHT for detail
##include /home/yuqing/fastdht/conf/fdht_servers.conf

# if log to access log
# default value is false
# since V4.00
use_access_log = false

# if rotate the access log every day
# default value is false
# since V4.00
rotate_access_log = false

# rotate access log time base, time format: Hour:Minute
# Hour from 0 to 23, Minute from 0 to 59
# default value is 00:00
# since V4.00
access_log_rotate_time = 00:00

# if compress the old access log by gzip
# default value is false
# since V6.04
compress_old_access_log = false

# compress the access log days before
# default value is 1
# since V6.04
compress_access_log_days_before = 7

# if rotate the error log every day
# default value is false
# since V4.02
rotate_error_log = false

# rotate error log time base, time format: Hour:Minute
# Hour from 0 to 23, Minute from 0 to 59
# default value is 00:00
# since V4.02
error_log_rotate_time = 00:00

# if compress the old error log by gzip
# default value is false
# since V6.04
compress_old_error_log = false

# compress the error log days before
# default value is 1
# since V6.04
compress_error_log_days_before = 7

# rotate access log when the log file exceeds this size
# 0 means never rotates log file by log file size
# default value is 0
# since V4.02
rotate_access_log_size = 0

# rotate error log when the log file exceeds this size
# 0 means never rotates log file by log file size
# default value is 0
# since V4.02
rotate_error_log_size = 0

# keep days of the log files
# 0 means do not delete old log files
# default value is 0
log_file_keep_days = 0

# if skip the invalid record when sync file
# default value is false
# since V4.02
file_sync_skip_invalid_record = false

# if use connection pool
# default value is false
# since V4.05
use_connection_pool = true

# connections whose the idle time exceeds this time will be closed
# unit: second
# default value is 3600
# since V4.05
connection_pool_max_idle_time = 3600

# if compress the binlog files by gzip
# default value is false
# since V6.01
compress_binlog = true

# try to compress binlog time, time format: Hour:Minute
# Hour from 0 to 23, Minute from 0 to 59
# default value is 01:30
# since V6.01
compress_binlog_time = 01:30

# if check the mark of store path to prevent confusion
# recommend to set this parameter to true
# if two storage servers (instances) MUST use a same store path for
# some specific purposes, you should set this parameter to false
# default value is true
# since V6.03
check_store_path_mark = true

# use the ip address of this storage server if domain_name is empty,
# else this domain name will ocur in the url redirected by the tracker server
http.domain_name =

# the port of the web server on this storage server
http.server_port = 8888

1.4 client.conf

# connect timeout in seconds
# default value is 30s
# Note: in the intranet network (LAN), 2 seconds is enough.
connect_timeout = 5

# network timeout in seconds
# default value is 30s
network_timeout = 60

# the base path to store log files
base_path = /mnt/e/ubuntu/client

# tracker_server can ocur more than once for multi tracker servers.
# the value format of tracker_server is "HOST:PORT",
#   the HOST can be hostname or ip address,
#   and the HOST can be dual IPs or hostnames seperated by comma,
#   the dual IPS must be an inner (intranet) IP and an outer (extranet) IP,
#   or two different types of inner (intranet) IPs.
#   for example: 192.168.2.100,122.244.141.46:22122
#   another eg.: 192.168.1.10,172.17.4.21:22122

tracker_server = 172.28.123.249:22122
#tracker_server = 192.168.0.197:22122

#standard log level as syslog, case insensitive, value list:
### emerg for emergency
### alert
### crit for critical
### error
### warn for warning
### notice
### info
### debug
log_level = info

# if use connection pool
# default value is false
# since V4.05
use_connection_pool = false

# connections whose the idle time exceeds this time will be closed
# unit: second
# default value is 3600
# since V4.05
connection_pool_max_idle_time = 3600

# if load FastDFS parameters from tracker server
# since V4.05
# default value is false
load_fdfs_parameters_from_tracker = false

# if use storage ID instead of IP address
# same as tracker.conf
# valid only when load_fdfs_parameters_from_tracker is false
# default value is false
# since V4.05
use_storage_id = false

# specify storage ids filename, can use relative or absolute path
# same as tracker.conf
# valid only when load_fdfs_parameters_from_tracker is false
# since V4.05
storage_ids_filename = storage_ids.conf


#HTTP settings
http.tracker_server_port = 80

#use "#include" directive to include HTTP other settiongs
##include http.conf
  • 启动

    sudo fdfs_trackerd /mnt/e/Code/CVIP/code/fastfds/tracker.conf
    sudo fdfs_storaged /mnt/e/Code/CVIP/code/fastfds/storage.conf
    
  • 测试

    # 查看服务
    fdfs_monitor /mnt/e/Code/CVIP/code/fastfds/client.conf
    # 上传
    fdfs_upload_file /mnt/e/Code/CVIP/code/fastfds/client.conf ./README.md
    # 下载
    fdfs_download_file /mnt/e/Code/CVIP/code/fastfds/client.conf group1/M00/00/00/rBx7-V_MGuWAF1sJAANQ-lXzICY3210.md
    # 删除
    fdfs_delete_file /mnt/e/Code/CVIP/code/fastfds/client.conf group1/M00/00/00/rBx7-V_MGuWAF1sJAANQ-lXzICY3210.md
    

2.FastCGI

2.1 CGI工作方式

  • 传统CGI(Common Gateway Interface)方式是客户端有多少个请求,就开辟多少个子进程,每个子进程都需要启动自己的解释器、加载配置,连接其他服务器等初始化工作,这是CGI进程性能低下的主要原因。当用户请求非常多的时候,会占用大量的内存、cpu等资源,造成性能低下。

    cgi工作方式

  • 与为每个请求创建一个新的进程不同,FastCGI使用持续的进程来处理一连串的请求。这些进程由 FastCGI进程管理器管理,而不是web服务器。

    fastcgi工作方式

  • 由于FastCGI程序并不需要不断的产生新进程,可以大大降低服务器的压力并且产生较高的应用效率。它的速度效率最少要比CGI技术提高5倍以上。它还支持分布式的部署,即FastCGI程序可以在web服务器以外的主机上执行。

2.2 spawn-fcgi

  • spawn-fcgi是一个通用的FastCGI进程管理器,简单小巧。

  • spawn-fcgi使用pre-fork模型,功能主要是打开监听端口,绑定地址,然后fork-and-exec创建我们编写的FastCGI应用程序进程,退出完成工作。FastCGI应用程序初始化,然后进入死循环侦听socket的连接请求。

  • 编译安装spawn-fcgi

    wget http://download.lighttpd.net/spawn-fcgi/releases-1.6.x/spawn-fcgi-1.6.4.tar.gz
    tar -zxvf spawn-fcgi-1.6.4.tar.gz
    cd spawn-fcgi-1.6.4/
    ./configure
    make -j 8
    sudo make install
    #sudo ln -s /usr/local/lib/libfcgi.so.0 /usr/lib/libfcgi.so.0
    

2.3 fcgi

  • 使用C/C++编写FastCGI应用程序,可以使用FastCGI软件开发套件或者其它开发框架,如fcgi

  • 编译安装fcgi

    wget https://fossies.org/linux/www/old/fcgi-2.4.0.tar.gz
    tar -zxvf fcgi-2.4.0.tar.gz
    cd fcgi-2.4.0/
    ./configure
    make -j 8
    sudo make install
    
  • fcgil例子

    /*
     * @Author: gongluck 
     * @Date: 2020-12-06 09:31:16 
     * @Last Modified by: gongluck
     * @Last Modified time: 2020-12-06 10:36:28
     */
      
    // gcc test.c -lfcgi
    // spawn-fcgi -a 127.0.0.1 -p 8001 -f ./a.out
    /* nginx conf add
    location /test {
              fastcgi_pass 127.0.0.1:8001;
              fastcgi_index test;
              include /usr/local/nginx/conf/fastcgi.conf;
          }	
    */
      
    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <unistd.h>
    #include "fcgi_stdio.h"
      
    int main(int argc, char *argv[])
    {
        int count = 0;
        //阻塞等待并监听某个端口,等待Nginx将数据发过来
        while (FCGI_Accept() >= 0)
        {
            //如果想得到数据,需要从stdin去读,实际上从Nginx上去读
            //如果想上传数据,需要往stdout写,实际上是给Nginx写数据
            printf("Content-type: text/html\r\n");
            printf("\r\n");
            printf("<title>Fast CGI Hello!</title>");
            printf("<h1>Fast CGI Hello!</h1>");
            //SERVER_NAME:得到server的host名称
            printf("Request number %d running on host <i>%s</i>\n",
                   ++count, getenv("SERVER_NAME"));
        }
        return 0;
    }
    

Last modified on 2020-12-28