is empty" exit 0 fi # 两个变量判断是否相等 if [ "$var1" = "$var2" ]; then echo '$var1 eq $var2' else echo '$var1 not eq $var2' fi 文件的判别逻辑大全: --- -a file exists. -b file exists and is a block special file. -c file exists and is a character special file...
If the file already exists, it opens the file in write mode, and the timestamp of the file is updated. 如果文件已经存在,它将以写入模式打开文件,并且文件的时间戳将更新。 mv(mv) Once you have a file, you can move it around using themvcommand. You specify the file current path, and it...
Copy file1 to file2 preserving the mode, ownership and timestamp. $ cp -p file1 file2 Copy file1 to file2. if file2 exists prompt for confirmation before overwritting it. $ cp -i file1 file2 29. mv command examples Rename file1 to file2. if file2 exists prompt for confirmation b...
Copy file1 to file2. if file2 exists prompt for confirmation before overwritting it. $ cp -i file1 file2 29. mv command examples Rename file1 to file2. if file2 exists prompt for confirmation before overwritting it. $ mv -i file1 file2 Note: mv -f is just the opposite, which ...
# File: simpleif.sh echo "Start program" if [[ $1 -eq 4 ]] then echo "You entered $1" fi echo "End program" First this program will print “Start program”, then the IF statement will check if the conditional expression[[ $1 -eq 4 ]]is true. It will only be true if you ...
cout<<"Key "<<key<<" already exists in bucket "<<bucket_id(bucket_no)<<endl; } } gdbm的实现 在gnu的gdbm实现中,可以看到函数主体是在一个while循环中,这也意味着在一次split调用中,可能会执行多次分裂。 ///@file: gdbm\src\bucket.c/* Split the current bucket. This includes moving all ite...
* CHECK if the file /etc/hosts.equiv is required. If you are running "r" commands, this file allows other hosts to be trusted by your system. Programs such as rlogin can then be used to log on to the same account name on your machine from a trusted machine without supplying a ...
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To boot an old kernel if the new kernel doesn't boot, stop the boot at during the count down. # unload # load kernel.old # boot System mount points/Disk usage # mount | column -t# Show mounted file-systems on the system# df# display free disk space and mounted devices# cat /proc...
Open the file in read only mode. $ vim -R /etc/passwd More vim examples:How To Record and Play in Vim Editor 8. diff command examples Ignore white space while comparing. # diff -w name_list.txt name_list_new.txt 2c2,3 < John Doe --- > John M Doe ...