remove extra \ in perl example

[rrdtool.git] / doc / rrd-beginners.pod

diff --git a/doc/rrd-beginners.pod b/doc/rrd-beginners.pod
index 37145e6..1c28515 100644 (file)
--- a/doc/rrd-beginners.pod
+++ b/doc/rrd-beginners.pod
@@ -1,4 +1,4 @@
-=head1 NAME 
+=head1 NAME
 
 rrd-beginners - RRDtool Beginners' Guide
 
@@ -58,8 +58,8 @@ data flow to update the RRDtool database.
 =back
 
 RRDtool is designed to store time series of data. With every data
-update, an assosiated time stamp is stored. Time is always expressed
-in seconds passed since epoch (01-01-1971). RRDtool can be installed
+update, an associated time stamp is stored. Time is always expressed
+in seconds passed since epoch (01-01-1970). RRDtool can be installed
 on Unix as well as Windows. It comes with a command set to carry out
 various operations on RRD databases. This command set can be accessed
 from the command line, as well as from Shell or Perl scripts. The
@@ -135,9 +135,9 @@ explained better with the following example:
 
  Values       = 300, 600, 900, 1200
  Step         = 300 seconds
- COUNTER DS   =    1,  1,   1,    1 
+ COUNTER DS   =    1,  1,   1,    1
  DERIVE DS    =    1,  1,   1,    1
- ABSOLUTE DS  =    1,  2,   3,    4 
+ ABSOLUTE DS  =    1,  2,   3,    4
  GAUGE DS     = 300, 600, 900, 1200
 
 The next parameter is B<heartbeat>. In our example, heartbeat is 600
@@ -149,7 +149,7 @@ is much better than to assume a missing value was 0 (zero) or any
 other number which might also be a valid data value.  For example, the
 traffic flow counter on a router keeps increasing. Lets say, a value
 is missed for an interval and 0 is stored instead of UNKNOWN. Now when
-hte next value becomes available, it will calculate the difference
+the next value becomes available, it will calculate the difference
 between the current value and the previous value (0) which is not
 correct. So, inserting the value UNKNOWN makes much more sense here.
 
@@ -251,7 +251,7 @@ generation is done using Perl scripts. These scripts are shown below:
 =head3 Perl script (retrieves data from database and generates graphs and statistics)
 
  #!/usr/bin/perl -w
- # This script fetches data from target.rrd, creates a graph of memory 
+ # This script fetches data from target.rrd, creates a graph of memory
  # consumption on the target (Dual P3 Processor 1 GHz, 656 MB RAM)
 
  # call the RRD perl module
@@ -262,8 +262,8 @@ generation is done using Perl scripts. These scripts are shown below:
  my $start_time = $end_time - 2592000; # set start 30 days in the past
 
  # fetch average values from the RRD database between start and end time
- my ($start,$step,$ds_names,$data) = 
-     RRDs::fetch("target.rrd", "AVERAGE", 
+ my ($start,$step,$ds_names,$data) =
+     RRDs::fetch("target.rrd", "AVERAGE",
                  "-r", "600", "-s", "$start_time", "-e", "$end_time");
  # save fetched values in a 2-dimensional array
  my $rows = 0;
@@ -292,26 +292,26 @@ generation is done using Perl scripts. These scripts are shown below:
  # calculate the average of the array
  my $tot_mem_ave = $tot_mem_sum/($count);
  # create the graph
- RRDs::graph ("/images/mem_$count.png",   \
-             "--title= Memory Usage",    \
-             "--vertical-label=Memory Consumption (MB)", \
-             "--start=$start_time",      \
-             "--end=$end_time",          \
-             "--color=BACK#CCCCCC",      \
-             "--color=CANVAS#CCFFFF",    \
-             "--color=SHADEB#9999CC",    \
-             "--height=125",             \
-             "--upper-limit=656",       \
-             "--lower-limit=0",          \
-             "--rigid",                  \
-             "--base=1024",              \
-             "DEF:tot_mem=target.rrd:mem:AVERAGE", \
-             "CDEF:tot_mem_cor=tot_mem,0,671744,LIMIT,UN,0,tot_mem,IF,1024,/",\
-             "CDEF:machine_mem=tot_mem,656,+,tot_mem,-",\
-             "COMMENT:Memory Consumption between $start_time",\
-             "COMMENT:    and $end_time                     ",\
-             "HRULE:656#000000:Maximum Available Memory - 656 MB",\
-             "AREA:machine_mem#CCFFFF:Memory Unused",   \
+ RRDs::graph ("/images/mem_$count.png",   
+             "--title= Memory Usage",    
+             "--vertical-label=Memory Consumption (MB)", 
+             "--start=$start_time",      
+             "--end=$end_time",          
+             "--color=BACK#CCCCCC",      
+             "--color=CANVAS#CCFFFF",    
+             "--color=SHADEB#9999CC",    
+             "--height=125",             
+             "--upper-limit=656",       
+             "--lower-limit=0",          
+             "--rigid",                  
+             "--base=1024",              
+             "DEF:tot_mem=target.rrd:mem:AVERAGE", 
+             "CDEF:tot_mem_cor=tot_mem,0,671744,LIMIT,UN,0,tot_mem,IF,1024,/",
+             "CDEF:machine_mem=tot_mem,656,+,tot_mem,-",
+             "COMMENT:Memory Consumption between $start_time",
+             "COMMENT:    and $end_time                     ",
+             "HRULE:656#000000:Maximum Available Memory - 656 MB",
+             "AREA:machine_mem#CCFFFF:Memory Unused",   
              "AREA:tot_mem_cor#6699CC:Total memory consumed in MB");
  my $err=RRDs::error;
  if ($err) {print "problem generating the graph: $err\n";}