shell if

Shell if-B Returns True when file exists and is a block file-C Returns True when file exists and is a character-D returns True when pathname exists and is a directory-E Returns True when a file or directory specified by pathname is present-F Returns

Original address: http://blog.chinaunix.net/uid-24607609-id-2118151.htmlThe syntax for the most streamlined if command is:if TEST-COMMANDS; then CONSEQUENT-COMMANDS; fiafter the Test-command executes and its return status is 0, the

/********************************************************************* * Makefile How to use shell if judgment * Description: * For example, it may be necessary to determine the existence of files, folders in Makfile, use shell syntax * To output

Linux Shell if parameterUsed in shell programming to determine parameters within an if statement–b return True when file exists and is a block file-C Returns True when file exists and is a character-D returns True when pathname exists and is a

Primary Meaning [- File] True ifFileExists. [-B File] True ifFileExists and is a block-special file. [-C File] True ifFileExists and is a character-special file. [-D File] True ifFileExists and

[Shell] if common judgment ConditionsIF you have written a simple shell script before the judgment, it is not a job O & M, and the work related to the system is relatively small, so it is not very skilled.Recently, as the system has encountered

[Shell] if common judgment conditions and shellif judgment ConditionsIF judgmentI have also written a simple shell script before, and it is not transferred to O & M. It has less work related to the system, so it is not very skilled.Recently, as the

[ -a file] is true if file exists. [ -b file] True if file exists and is a block special file. [ -c file] True if file exists and is a word special. [ -d file] True if file exists and is a directory. [ -e file] is true if file exists. [ -f file]

if [$#! = 1]; Thenecho "USAGE: $ tabname"echo "e.g.: $ cdr_call_20040701"Exit 1;FiLocation parameters $ #代表了命令行的参数数量, $ $,..., $N, and $ A represents the name of the script-ne Not equal to-----------------------Used in shell programming to determine

If usage:if []; thenCommandelif []; thenCommandElseCommandFiIf parameter:Used in shell programming to determine parameters within an if statement–b return True when file exists and is a block file-C Returns True when file exists and is a character-D

[ -a FILE]  如果 FILE存在则为真。  [ -b FILE]  如果 FILE存在且是一个块特殊文件则为真。  [ -c FILE

If condition test common syntax Test [] [[]] ()) Test command AND [] testing operator Test [] (these two syntaxes are equivalent) test operator full Spell

If statement 1.1 if statement explanation If is a judgment statement, if the action is similar to [], the general judgment is more or the execution of the statement is more, then will use if 1.2 If format First format if [

In linux shell if parameter shell programming, the if statement is used to determine the parameter www.2cto.com-B. When the file exists and is a block file, true-c is returned when the file exists and is a character file. -d. When pathname exists

From http://vc88.javaeye.com/blog/658764   Shell if interpretation statement[Front and back Spaces] Leading space[-A file] true if the file exists.[-B file] If the file exists and is a special block file, it is true.[-C file] If the file exists

Used in shell programming to determine parameters within an if statement–b return True when file exists and is a block file-C Returns True when file exists and is a character-D returns True when pathname exists and is a directory-E Returns True when

No matter what programming language is inseparable from conditional judgment. The shell is no exception.The approximate format is as follows:If List ThenDo something hereElif List ThenDo another thing hereElseDo something else hereFiAn

The conditional judgment statement in the shell is an upgrade to the previous "conditional test statement in the shell", meaning that the preceding test statement serves the IF~THEN~FI statement for the current judgment statement.We're still rolling

The IF statement determines which branch to execute by using relational operators to determine whether an expression is true or false. The Shell has three kinds of if ... else statements: If ... fi statement; If ... else ... fi

The IF statement determines which branch to execute by using relational operators to determine whether an expression is true or false. The Shell has three kinds of if ... else statements: If ... fi statement; If ... else ... fi