Re: Read and parse text file

#!perl
open (FILEH, "/etc/passwd");  #open the file for read
while (<FILEH>) {  #while there are still lines in FILEH...
chomp;  #clear newlines...
  if ( /root/i ) {  # if line contains "root" case insensitive`
        ($username,$id) = (split /:/)[0,2]; #pull out field one and th
+ree
        print "User: $username,  ID: $id\n";  #print junk
   }
}
[download]

this is similar to the unix commands:

grep -i root /etc/passwd | awk '{ ...

You can figure it out.
[download]

-Waswas

Comment on Re: Read and parse text file Select or Download Code

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Re: Re: Read and parse text file by RCP (Acolyte) on Feb 24, 2004 at 12:40 UTC
Thanks for the short code, it's exaclly what I was looking for. My unix scripts finds specific files generated by a software's report, extracts specific data from columns and writes out a "macros" to execute within the software. I was supposed to start PERL class next week, but heart surgery cut that short, now I have something to do while I'm at home recuperating. Thanks! RCP	[reply]
Re: Re: Read and parse text file by RCP (Acolyte) on Mar 08, 2004 at 18:23 UTC
#!perl open (FILEH, "/etc/passwd"); #open the file for read while (<FILEH>) { #while there are still lines in FILEH... chomp; #clear newlines... if ( /root/i ) { # if line contains "root" case insensitive` ($username,$id) = (split /:/)[0,2]; #pull out field one and th +ree print "User: $username, ID: $id\n"; #print junk } } [download] Thanks again for your help earlier. I was wondering if there was a way to have this script read each line in a file and if there is not a fourth column, do not write that line out. If there is a fourth column, then write the line out. Thanks, RCP	[reply] [d/l]
Re^3: Read and parse text file by Roy Johnson (Monsignor) on Mar 08, 2004 at 18:28 UTC
If you're splitting on ':', `while (<>) { print if tr/:// >= 3; # Special use of tr to count column separato +rs }` [download] To count columns more literally, and splitting on the more traditional whitespace: `while (<>) { my @cols = split; print if @cols >= 4; }` [download] The PerlMonk `tr///` Advocate	[reply] [d/l] [select]
Re: Re^3: Read and parse text file by RCP (Acolyte) on Mar 09, 2004 at 14:36 UTC
Your second approach worked much better! Thanks again... RCP	[reply]