Sponsored Content
Full Discussion: Copy file only if newer
Top Forums Shell Programming and Scripting Copy file only if newer Post 303024490 by Don Cragun on Tuesday 9th of October 2018 04:16:02 PM
Old 10-09-2018
Yes, the test utility operator -nt stands for newer than. If you check the man page for the test utility on your system or look for the term "conditional expression" on the man page for your shell, you'll find lots of useful tests that can be performed in your shell scripts. (Note that "conditional expression" might be all lowercase, all uppercase, or have the first letter of each word capitalized depending on which shell's man page you're reading.)

Most of the operators that are available with the [[ command (if your shell has a [[ command) are also available with the test utility invoked with:
Code:
test expression

or with:
Code:
[ expression ]

The test and [ utilities are available with all Bourne shell derived shells.
 

9 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

tar --newer = tar --newer-mtime ?

Hi, I have the following question : As far as I know unix doesn't store file creation dates. Would that imply the following? tar -cvzf backup.tar --newer is equal to: tar -cvzf backup.tar --newer-mtime ? (1 Reply)
Discussion started by: jamesbond
1 Replies

2. Shell Programming and Scripting

copy only newer files? (xcopy equivalent)

Howdy folks. I have a problem - I'm sure the answer is very simple, but I can't work it out. I want to create a UNIX shell script that does what I've been doing in DOS batch files for years - that is, backing up files. By which I mean copying files from a source directory to a target... (4 Replies)
Discussion started by: Chomps
4 Replies

3. Solaris

To copy the files newer than specific date

Dear all, Can you help me in copying files newer than speciifc date Thanks in advance, Rajesh (3 Replies)
Discussion started by: RAJESHKANNA
3 Replies

4. Shell Programming and Scripting

Copy newer files without create

I want the same effect as "cp -u" but without create missing files, it is possible ? ps: bash (2 Replies)
Discussion started by: mrxrsd
2 Replies

5. Shell Programming and Scripting

If condition to check one file newer than the other - first file name uncertain

Dear All, I'm new to unix scripting. I'm trying to write an utility script which has to check if one file is newer than another one. The condition is I dont know the full name of the first file. I searched google and this forum for any such examples, but couldn't find any or may be I would have... (9 Replies)
Discussion started by: achilles5
9 Replies

6. Shell Programming and Scripting

How to script to find the newer date in a text file?

Hi, I have a text file, foo.txt, it looks something like below. In the file there is a line that gives the date in the form of: Mon Jun 15 11:09:31 2008. I need to find which date is the newest and then store certain details of that list data to another file. So, in this sample text file, I... (6 Replies)
Discussion started by: boolean2222
6 Replies

7. Shell Programming and Scripting

how to find a file then overwrite with a newer version

This should be a simple script, but can't find one with google search. I just need to find the file that is in many directories, then overwrite that file with a newer version i.e. find file.jar then overwrite with /root/file.jar All I get in searches is substitute text with new test inside... (1 Reply)
Discussion started by: haircat
1 Replies

8. Shell Programming and Scripting

Perl script, replace file with newer file

Hello, Can you please help me one this: I have two servers: Server A and server B. Every day on 03.00AM in only one on these two servers (randomly)is generated one file, lets say file.txt. I want to copy this file also to the other server. I want to create a perl script that does... (2 Replies)
Discussion started by: arrals_vl
2 Replies

9. UNIX for Dummies Questions & Answers

If condition to check one file newer than the other

Dear All, I'm new to unix scripting. I'm trying to write an utility script which has to check if one file is newer than another one. $3 $4 $5 $6 are files .txt. Help me please. for i in $3 $4 $5 $6 do if then echo "$1 is newer than $i" else echo "$i is newer than $1" fi (9 Replies)
Discussion started by: Manueldo
9 Replies
test(1B)					     SunOS/BSD Compatibility Package Commands						  test(1B)

NAME
test - condition evaluation command SYNOPSIS
/usr/ucb/test expression expression DESCRIPTION
test evaluates the expression expression and, if its value is true, sets 0 (true) exit status; otherwise, a non-zero (false) exit status is set. test also sets a non-zero exit status if there are no arguments. When permissions are tested, the effective user ID of the process is used. All operators, flags, and brackets (brackets used as shown in the second SYNOPSIS line) must be separate arguments to the test command; normally these items are separated by spaces. USAGE
Primitives The following primitives are used to construct expression: -r filename True if filename exists and is readable. -w filename True if filename exists and is writable. -x filename True if filename exists and is executable. -f filename True if filename exists and is a regular file. Alternatively, if /usr/bin/sh users specify /usr/ucb before /usr/bin in their PATH environment variable, then test will return true if filename exists and is (not-a-directory). This is also the default for /usr/bin/csh users. -d filename True if filename exists and is a directory. -c filename True if filename exists and is a character special file. -b filename True if filename exists and is a block special file. -p filename True if filename exists and is a named pipe (fifo). -u filename True if filename exists and its set-user- ID bit is set. -g filename True if filename exists and its set-group- ID bit is set. -k filename True if filename exists and its sticky bit is set. -s filename True if filename exists and has a size greater than zero. -t[ fildes ] True if the open file whose file descriptor number is fildes (1 by default) is associated with a terminal device. -z s1 True if the length of string s1 is zero. -n s1 True if the length of the string s1 is non-zero. s1 = s2 True if strings s1 and s2 are identical. s1 != s2 True if strings s1 and s2 are not identical. s1 True if s1 is not the null string. n1 -eq n2 True if the integers n1 and n2 are algebraically equal. Any of the comparisons -ne, -gt, -ge, -lt, and -le may be used in place of -eq. Operators These primaries may be combined with the following operators: ! Unary negation operator. -a Binary and operator. -o Binary or operator (-a has higher precedence than -o). (expression) Parentheses for grouping. Notice also that parentheses are meaningful to the shell and, therefore, must be quoted. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWscpu | +-----------------------------+-----------------------------+ SEE ALSO
find(1), sh(1), attributes(5) NOTES
The not-a-directory alternative to the -f option is a transition aid for BSD applications and may not be supported in future releases. If you test a file you own (the -r , -w , or -x tests), but the permission tested does not have the owner bit set, a non-zero (false) exit status will be returned even though the file may have the group or other bit set for that permission. The correct exit status will be set if you are super-user. The = and != operators have a higher precedence than the -r through -n operators, and = and != always expect arguments; therefore, = and != cannot be used with the -r through -n operators. If more than one argument follows the -r through -n operators, only the first argument is examined; the others are ignored, unless a -a or a -o is the second argument. SunOS 5.11 1 Apr 1996 test(1B)
All times are GMT -4. The time now is 09:15 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy