diff --git a/bin/pt-ioprofile b/bin/pt-ioprofile
index c6c63494..c9bb3c99 100755
--- a/bin/pt-ioprofile
+++ b/bin/pt-ioprofile
@@ -441,10 +441,44 @@ rm_tmpdir() {
 # End tmpdir package
 # ###########################################################################
 
+# ###########################################################################
+# alt_cmds package
+# ###########################################################################
+
+# seq N, return 1, ..., 5
+_seq() {
+   local i="$1"
+   awk "BEGIN { for(i=1; i<=$i; i++) print i; }"
+}
+
+_pidof() {
+   local cmd="$1"
+   if ! pidof "$cmd" 2>/dev/null; then
+      ps -eo pid,ucomm | awk -v comm="$cmd" '$2 == comm { print $1 }'
+   fi
+}
+
+_lsof() {
+   local pid="$1"
+   if ! lsof -p $pid 2>/dev/null; then
+      /bin/ls -l /proc/$pid/fd 2>/dev/null
+   fi
+}
+
+_which() {
+   # which on CentOS is aliased to a cmd that prints extra stuff.
+   # Also, if the cmd isn't found, a msg is printed to stderr.
+   [ -x /usr/bin/which ] && /usr/bin/which "$1" 2>/dev/null | awk '{print $1}'
+}
+
+# ###########################################################################
+# End alt_cmds package
+# ###########################################################################
+
 # ###########################################################################
 # Global variables
 # ###########################################################################
-TOOL=`basename $0`
+TOOL="pt-ioprofile"
 
 # ###########################################################################
 # Subroutines
@@ -454,8 +488,6 @@ TOOL=`basename $0`
 # pid function fd_no size timing filename
 # The arguments are the files to summarize.
 tabulate_strace() {
-   local file="$1"
-
    cat > $TMPDIR/tabulate_strace.awk <<EOF
    BEGIN {
       # These are function names, or partial function names, that we care about.
@@ -553,7 +585,7 @@ tabulate_strace() {
       }
    }
 EOF
-   awk -f $TMPDIR/tabulate_strace.awk "$file"
+   awk -f $TMPDIR/tabulate_strace.awk "$@"
 }
 
 # Takes as input the output from tabulate_strace.  Arguments are just a subset
@@ -565,7 +597,7 @@ summarize_strace() {
    local group_by="$3"
    local file="$4"
 
-   cat > $TMPDIR/summarize_strace.awk <<EOF
+   cat > "$TMPDIR/summarize_strace.awk" <<EOF
    BEGIN {
       # These are function names, or partial function names, that we care about.
       # Later we will ignore any function whose name doesn't look like these.
@@ -687,7 +719,10 @@ EOF
 }
 
 main() {
-   if [ $# -eq 0 ]; then
+   if [ $# -gt 0 ]; then
+      # Summarize the files the user passed in.
+      tabulate_strace "$@" > $TMPDIR/tabulated_samples
+   else
       # There's no file to analyze, so we'll make one.
       if which strace > /dev/null 2>&1; then
 
@@ -697,13 +732,7 @@ main() {
          # gave us it explicitly with --profile-pid.
          local proc_pid="$OPT_PROFILE_PID"
          if [ -z "$proc_pid" ]; then
-            proc_pid=$(pidof -s "$OPT_PROFILE_PROCESS" 2>/dev/null);
-            if [ -z "$proc_pid" ]; then
-               proc_pid=$(pgrep -o -x "$OPT_PROFILE_PROCESS" 2>/dev/null)
-            fi
-            if [ -z "$proc_pid" ]; then
-               proc_pid=$(ps -eaf | grep "$OPT_PROFILE_PROCESS" | grep -v grep | awk '{print $2}' | head -n1);
-            fi
+            proc_pid=$(_pidof "$OPT_PROFILE_PROCESS" | awk '{print $1; exit;'})
          fi
 
          date
@@ -711,7 +740,7 @@ main() {
          if [ "$proc_pid" ]; then
             echo "Tracing process ID $proc_pid"
 
-            lsof -n -P -s -p "$proc_pid" > "$samples" 2>&1
+            _lsof "$proc_pid" > "$samples" 2>&1
             if [ "$?" -ne "0" ]; then
                echo "Error: could not execute lsof, error code $?"
                exit 1
@@ -756,32 +785,36 @@ main() {
          echo "strace is not in PATH" >&2
          exit 1
       fi
-   else
-      # Summarize the files the user passed in.
-      tabulate_strace "$@" > $TMPDIR/tabulated_samples
    fi
 
    summarize_strace  \
       $OPT_AGGREGATE \
       $OPT_CELL      \
       $OPT_GROUP_BY  \
-      $TMPDIR/tabulated_samples
+      "$TMPDIR/tabulated_samples"
 }
 
 # Execute the program if it was not included from another file.
 # This makes it possible to include without executing, and thus test.
-if    [ "$(basename "$0")" = "pt-ioprofile" ] \
-   || [ "$(basename "$0")" = "bash" -a "$_" = "$0" ]; then
+if    [ "${0##*/}" = "$TOOL" ] \
+   || [ "${0##*/}" = "bash" -a "$_" = "$0" ]; then
 
    # Parse command line options.  We must do this first so we can
    # see if --daemonize was specified.
    mk_tmpdir
-   parse_options $0 "$@"
-   usage_or_errors $0
-   EXIT_STATUS=$?
-   if [ $EXIT_STATUS -eq 0 ]; then
-      # No errors parsing command line options, run the program.
-      main "$EXT_ARGV"
+   parse_options "$0" "$@"
+   usage_or_errors "$0"
+   po_status=$?
+   if [ $po_status -eq 0 ]; then
+      # XXX
+      # TODO: This should be quoted but because the way parse_options()
+      # currently works, it flattens files in $@ (i.e. given on the cmd
+      # line) into the string $ARGV.  So if we pass "$ARGV" then other
+      # functions will see 1 file named "file1 file2" instead of "file1"
+      # "file2".
+      main $ARGV
+   else
+      [ $OPT_ERRS -gt 0 ] && EXIT_STATUS=1
    fi
    rm_tmpdir
    exit $EXIT_STATUS
diff --git a/t/pt-ioprofile/pt-ioprofile.t b/t/pt-ioprofile/pt-ioprofile.t
index a690ecdb..63aeb2d4 100644
--- a/t/pt-ioprofile/pt-ioprofile.t
+++ b/t/pt-ioprofile/pt-ioprofile.t
@@ -9,16 +9,53 @@ BEGIN {
 use strict;
 use warnings FATAL => 'all';
 use English qw(-no_match_vars);
+use Test::More;
+use Time::HiRes qw(time);
 
 use PerconaTest;
+use DSNParser;
+use Sandbox;
 
-my ($tool) = $PROGRAM_NAME =~ m/([\w-]+)\.t$/;
-push @ARGV, "$trunk/t/$tool/*.sh" unless @ARGV;
+my $dp = new DSNParser(opts=>$dsn_opts);
+my $sb = new Sandbox(basedir => '/tmp', DSNParser => $dp);
+my $dbh = $sb->get_dbh_for('master');
 
-$ENV{BIN_DIR} = "$trunk/bin";
-$ENV{T_DIR}   = "$trunk/t/$tool";
+if ( !$dbh ) {
+   plan skip_all => "Cannot connect to master sandbox";
+}
+else {
+   plan tests => 3;
+}
 
-system("$trunk/util/test-bash-functions $trunk/t/lib/samples/bash/dummy.sh @ARGV");
+my $output = "";
+
+$output = `$trunk/bin/pt-ioprofile --help 2>&1`;
+like(
+   $output,
+   qr/--version/,
+   "--help"
+);
+
+
+my $t0 = time;
+$output = `$trunk/bin/pt-ioprofile --run-time 3 2>&1`;
+my $t1 = time;
+
+like(
+   $output,
+   qr/Tracing process ID \d+/,
+   "Runs without a file (bug 925778)"
+);
+
+# If the system is really slow, it may take a second to process the files
+# and then clean up all the temp stuff.  In any case, the default run-time
+# is 30s so it should be way less than that.
+cmp_ok(
+   $t1 - $t0,
+   '<',
+   5,
+   "Runs for --run-time"
+);
 
 # #############################################################################
 # Done.
diff --git a/t/pt-ioprofile/samples/003-processed.txt b/t/pt-ioprofile/samples/003-processed.txt
new file mode 100644
index 00000000..b04a1c28
--- /dev/null
+++ b/t/pt-ioprofile/samples/003-processed.txt
@@ -0,0 +1,5 @@
+     total      pread       read       open      close getdents64    _llseek filename
+  0.006348   0.006348   0.000000   0.000000   0.000000   0.000000   0.000000 /data/data/abd_2dia/aia_227_228.ibd
+  0.000504   0.000000   0.000000   0.000096   0.000098   0.000310   0.000000 /data/data/abd_2dia/
+  0.000369   0.000369   0.000000   0.000000   0.000000   0.000000   0.000000 /data/data/abd_2dia/aia_227_223.ibd
+  0.000288   0.000000   0.000062   0.000054   0.000045   0.000000   0.000127 /data/data/abd_2dia/test/db.opt
diff --git a/t/pt-ioprofile/saved_samples.t b/t/pt-ioprofile/saved_samples.t
new file mode 100644
index 00000000..41972363
--- /dev/null
+++ b/t/pt-ioprofile/saved_samples.t
@@ -0,0 +1,35 @@
+#!/usr/bin/env perl
+
+BEGIN {
+   die "The PERCONA_TOOLKIT_BRANCH environment variable is not set.\n"
+      unless $ENV{PERCONA_TOOLKIT_BRANCH} && -d $ENV{PERCONA_TOOLKIT_BRANCH};
+   unshift @INC, "$ENV{PERCONA_TOOLKIT_BRANCH}/lib";
+};
+
+use strict;
+use warnings FATAL => 'all';
+use English qw(-no_match_vars);
+use Test::More tests => 1;
+
+use PerconaTest;
+
+my $sample = "t/pt-ioprofile/samples";
+my $output = "";
+
+# Files with raw samples should be named N-samples.txt
+# in t/pt-ioprofile/samples/.
+foreach my $sampleno ( qw(003) ) {
+   ok(
+      no_diff(
+         "$trunk/bin/pt-ioprofile $trunk/$sample/$sampleno-samples.txt",
+         "$sample/$sampleno-processed.txt",
+         stderr => 1,
+      ),
+      "$sampleno-samples.txt"
+   );
+}
+
+# #############################################################################
+# Done.
+# #############################################################################
+exit;
diff --git a/t/pt-ioprofile/unit_tests.pl b/t/pt-ioprofile/unit_tests.pl
new file mode 100644
index 00000000..582cfd3e
--- /dev/null
+++ b/t/pt-ioprofile/unit_tests.pl
@@ -0,0 +1,26 @@
+#!/usr/bin/env perl
+
+BEGIN {
+   die "The PERCONA_TOOLKIT_BRANCH environment variable is not set.\n"
+      unless $ENV{PERCONA_TOOLKIT_BRANCH} && -d $ENV{PERCONA_TOOLKIT_BRANCH};
+   unshift @INC, "$ENV{PERCONA_TOOLKIT_BRANCH}/lib";
+};
+
+use strict;
+use warnings FATAL => 'all';
+use English qw(-no_match_vars);
+
+use PerconaTest;
+
+my $tool = "pt-ioprofile";
+push @ARGV, "$trunk/t/$tool/*.sh" unless @ARGV;
+
+$ENV{BIN_DIR} = "$trunk/bin";
+$ENV{T_DIR}   = "$trunk/t/$tool";
+
+system("$trunk/util/test-bash-functions $trunk/t/lib/samples/bash/dummy.sh @ARGV");
+
+# #############################################################################
+# Done.
+# #############################################################################
+exit;