check_logfile: add example and update docs

Author: sni

docs/checks/commands/check_logfile.md

@@ -18,6 +18,13 @@ Checks logfiles or any other text format file for errors or other general patter
 
 ## Examples
 
+### Default Check
+
+Alert if there are errors in the snclient log file:
+
+    check_files files=/var/log/snclient/snclient.log 'warn=line like Warn' 'crit=line like Error'"
+    OK - All 1787 / 1787 Lines OK
+
 ### Example using NRPE and Naemon
 
 Naemon Config
@@ -31,7 +38,7 @@ Naemon Config
         host_name            testhost
         service_description  check_logfile
         use                  generic-service
-        check_command        check_nrpe!check_logfile!
+        check_command        check_nrpe!check_logfile!'files=/var/log/snclient/snclient.log' 'warn=line like Warn'
     }
 
 ## Argument Defaults

pkg/snclient/check_logfile.go

@@ -72,8 +72,12 @@ func (c *CheckLogFile) Build() *CheckData {
 			{name: "columnN", description: "Match the content of the N-th column only if enough columns exists"},
 		},
 		exampleDefault: `
-		`,
-		exampleArgs: ``,
+Alert if there are errors in the snclient log file:
+
+    check_files files=/var/log/snclient/snclient.log 'warn=line like Warn' 'crit=line like Error'"
+    OK - All 1787 / 1787 Lines OK
+	`,
+		exampleArgs: `'files=/var/log/snclient/snclient.log' 'warn=line like Warn'`,
 	}
 }
 

pkg/snclient/checkdata.go

@@ -297,17 +297,17 @@ func (cd *CheckData) buildListMacros() map[string]string {
 
 	// if there is only one problem, there is no need to add brackets
 	if len(critList) > 0 {
-		result["crit_list"] = "critical(" + strings.Join(critList, ", ") + ")"
+		result["crit_list"] = "critical(" + strings.Join(critList, cd.listCombine) + ")"
 		problemList = append(problemList, result["crit_list"])
 		detailList = append(detailList, result["crit_list"])
 	}
 	if len(warnList) > 0 {
-		result["warn_list"] = "warning(" + strings.Join(warnList, ", ") + ")"
+		result["warn_list"] = "warning(" + strings.Join(warnList, cd.listCombine) + ")"
 		problemList = append(problemList, result["warn_list"])
 		detailList = append(detailList, result["warn_list"])
 	}
 	if len(okList) > 0 {
-		result["ok_list"] = strings.Join(okList, ", ")
+		result["ok_list"] = strings.Join(okList, cd.listCombine)
 		detailList = append(detailList, result["ok_list"])
 	}