I have a problem with an if/else statement in bash.
I want to check if the file exists before running a task (for example here, counting lines), and if not I need to create an empty output file
Code:
if [ -f /input.tab ]
then
wc -l input.tab > output.temp
else
>output.temp
fi
The problem is even if the condition is true (the file actually exists) it goes directly to the else part and create an empty file in any case.
Could someone explain me what is wrong with my syntax... !!!
Does the file input.tab really exist in the root directory (/input.tab), or is it in the current directory (input.tab)? It would seem that you should use the same pathname in both the test and the wc commands.
This User Gave Thanks to Don Cragun For This Post:
Hello,
I wonder whether if we have a open file dialog as (in gtk+) in html. I know that a submit-type form (such as <input value="Add File" type="submit">) opens such dialog, but it -naturally- tries to submit the file chosen. I only want to find out the file name, not upload it.
Thanks! (0 Replies)
I'd like a bash script to simply check to see if any file/files are present in a source directory, and if so move it/them to a target directory.
I have this but it doesn't work:
#!/bin/bash
if
then
mv /source/* /target
fi
What is the right syntax? Thanks! (4 Replies)
Hello
I have srv RHEL5, file system UTDM (EMC DiskXtender Unix/Linux File System Manager 3.5 & EMC Centera).
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basically im trying to make this work in a bash shell script without using if statements
if
then
echo testfile exists!
fi
what it does is check if the file exists or not
i have this line but its not working, it checks if the testfile exists if it doesnt it 2> to the dev null... (3 Replies)
hello. this is the code
#!/bin/sh
total1024=0
total2048=0
total8192=0
if ; then
if ; then
while read variable
do
if ; then
total1024=$(( $total1024 + 1 ))
fi
if ; then
total2048=$((... (4 Replies)
Hey all,
Here's my dilemma:
1. I'm a newbie at scripting!
2. I need to create a script that checks: If a file size is equal to zero, then stop the installation.
Is there a way to do this or am I wasting my time???
Thanx in advance! :b: (2 Replies)
Hi
#Testing for file existence
if ; then
echo 'SCHOOL data is available for processing'
else
echo 'SCHOOL DATA IS NOT AVAILABLE FOR PROCESSING'
:
i wrote a script, where it begins by checking if file exists or not.
If it exists, it truncates the database... (2 Replies)
Hi!
I wanted to simplify my bash prompt, so I edited my etc/bashrc file. I thought this was the file that would override any other env files. When I opened it, I saw that the way it was setup was not what my prompt looked like, although I forget exactly what was there. But i edited it the way I... (1 Reply)
Hi All,
I am facing a problem while checking for existence of file over ssh !
Basically, i want to ssh and check if file exists.. If file exists return 1. If file does not exits return 0 (or any value)
I am using the below code
file_avail=`ssh username@host "if ]; then exit 1;... (10 Replies)
OK So I Recently Bought A whatbox Seed-box Act!!:cool:
I am connected to whatbox via SSH!!!
Now i have downloaded a movie and renamed it to 2yify.mp4 (800MB):o
When I TYPE the command to split it which is:)
split -b 400m 2yify.mp4
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Discussion started by: anime12345
4 Replies
LEARN ABOUT PLAN9
pr
PR(1) General Commands Manual PR(1)NAME
pr - print file
SYNOPSIS
pr [ option ... ] [ file ... ]
DESCRIPTION
Pr produces a printed listing of one or more files on its standard output. The output is separated into pages headed by a date, the name
of the file or a specified header, and the page number. With no file arguments, pr prints its standard input.
Options apply to all following files but may be reset between files:
-n Produce n-column output.
+n Begin printing with page n.
-b Balance columns on last page, in case of multi-column output.
-d Double space.
-en Set the tab stops for input text every n spaces.
-h Take the next argument as a page header (file by default).
-in Replace sequences of blanks in the output by tabs, using tab stops set every n spaces.
-f Use formfeeds to separate pages.
-ln Take the length of the page to be n lines instead of the default 66.
-m Print all files simultaneously, each in one column.
-n Number the lines of each file.
-on Offset the left margin n character positions.
-sc Separate columns by the single character c instead of aligning them with white space. A missing c is taken to be a tab.
-t Do not print the 5-line header or the 5-line trailer normally supplied for each page.
-wn For multi-column output, take the width of the page to be n characters instead of the default 72.
SOURCE
/sys/src/cmd/pr.c
SEE ALSO cat(1), lp(1)PR(1)
05-27-2013
!!!