Linux Ask! is a Q & A web site specific for Linux related questions. Questions are collected, answered and audited by experienced Linux users.
Calculate PHP script's execution time
Answer:
If you want to estimate the PHP script's execution time, you can try something like the following:
<?php
$time_start = microtime(true);
// some long running codes...
$time_end = microtime(true);
echo "Time (msec) passed: " , $time_end - $time_start;
How to set the filetype in Vim
Answer:
When you created a new file by using the command vi, vim does not know the file type unless you save the file with a specific extension, e.g. test.c, or sometimes when the extension cannot be recognized by vim, you need to set the file type manually in command mode - pressing Esc + :
:set filetype=c
That is it.
mount: unknown filesystem type 'nfs'
Answer:
If you attempt to mount a NFS share, using the mount command, e.g.
# sudo mount -t nfs 192.168.1.2:/data/share /mnt/share
And it gives:
mount: unknown filesystem type 'nfs'
You would need to install the nfs clients to solve it:
# sudo apt-get install nfs-common
Multi-line strings in Bash
Answer:
Bash support multiple line string, e.g.
#!/bin/bash
sort <<EOT
apple
orange
banna
EOT
When you execute the script,
# bash test.sh
It gives:
apple
banna
orange
Generate new list using map in Perl
Answer:
The Perl's map function is superb cool for generating new list based on an existing list.
1. Generate new array based on an existing array
my @new = map {$_ * 2} (1, 2, 3);
# @new contains 2, 4, 6
2. Generate new hash based on an existing array
my %new = map {$_ => 1} (1,2,3);
# %new contains a hash...
# {
# '1' => 1,
# '3' => 1,
# '2' => 1
# };
