Here I write about various events I was involved in and ideas that inspired me. Recently, it is more of a linux blog because I have been doing a lot of work on it. However, off and on I write on various other things that my mind just can't let go easily.
Monday, 29 June 2015
Monday, 27 April 2015
Finding remote URL of a folder under git
I was trying to recover an old codebase. I could see that it had two remotes one of which was now rejecting pushes. So, I figured the remote must have changed. To verify, I needed to see how to find out the remote URL. I found there are three ways of doing it as follows:
- git remote show remote_name # this failed for me as the remote URL was unavailable
- git config --get remote.heroku.url # this solved my purpose
- git remote -v # simplest of all to remember
Heroku suports only Ubuntu
Heroku supports Ubuntu nicely but seems to ignore other distributions. Their reference points to an OS-specific choice page.
That page provides a script and a command that uses the script to install heroku toolbet for Ubuntu.
However, even for standalone option, the script does not change.
Now standalone essentially is the category of other linux and BSD distributions. So, having an apt-get script for them is like saying "We hardly care about you". They could have provided a source link there. In fact given that another link on the same page links to their source hosted at Github. And interestingly their Github page asks to first install heroku toolbelt redirecting back to the same page.
![]() |
| points to toolbelt.heroku.com |
![]() | |
| Ubuntu option |
![]() |
| Standalone option |
![]() |
| deadlock completed |
Saturday, 4 April 2015
Saturday, 28 March 2015
Bad user experience on fortune.com
![]() |
| Experience in mobile and web should be different |
Saturday, 14 February 2015
Monday, 5 January 2015
Disruption in taxi business
Earlier taxi's used to be rather costly. Auto-rickshaws would be around half the price. So spending a little more time in travel and saving some money was a good option. However, looking at the fare charts of Ola and Taxi For Sure, it seems they are snatching away the market from auto-rickshaw drivers as well as from old taxi services.
Negotiating with auto-rickshaw drivers is a hard-learned skill. However as companies like Ola and Taxi For Sure are gaining market, the skill is becoming useless. The disruption in the market is achieved by use of technology to reduce wait time for taxis as well as customers.
The pain points that these technologies are addressing are:
1. Time spent in negotiation is cut off.
2. Taxi drivers are on an average better behaved than auto-rickshaw drivers.
3. Scheduling pickups is easier.
4. Payment is easy if you have a digital wallet with the taxi service.
Some issues that I face usually in Hyderabad are:
1. The driver does not know Hindi and I don't know Telugu so we are stuck on the communication part.
2. The time shown by these car service apps does not take into account the traffic.
3. The drivers usually don't know how to read maps. They need guidance to reach the pickup point and sometimes take long routes.
4. The mobile phone network is not consistent.
Often I find the driver knows a landmark near him and a landmark near my pickup point and because of language problem, I can't explain to him which way (possible shortcut) to take. So, instead of trying hard to explain, I tell him to start on the route he knows or a general route. Then I start tracking him to find where he is and call him back to tell him what to do.
Disruption in this market space is really a nice improvement. It is beneficial to customers as well as drivers. I hope to see this industry flourish.
Negotiating with auto-rickshaw drivers is a hard-learned skill. However as companies like Ola and Taxi For Sure are gaining market, the skill is becoming useless. The disruption in the market is achieved by use of technology to reduce wait time for taxis as well as customers.
The pain points that these technologies are addressing are:
1. Time spent in negotiation is cut off.
2. Taxi drivers are on an average better behaved than auto-rickshaw drivers.
3. Scheduling pickups is easier.
4. Payment is easy if you have a digital wallet with the taxi service.
Some issues that I face usually in Hyderabad are:
1. The driver does not know Hindi and I don't know Telugu so we are stuck on the communication part.
2. The time shown by these car service apps does not take into account the traffic.
3. The drivers usually don't know how to read maps. They need guidance to reach the pickup point and sometimes take long routes.
4. The mobile phone network is not consistent.
Often I find the driver knows a landmark near him and a landmark near my pickup point and because of language problem, I can't explain to him which way (possible shortcut) to take. So, instead of trying hard to explain, I tell him to start on the route he knows or a general route. Then I start tracking him to find where he is and call him back to tell him what to do.
Disruption in this market space is really a nice improvement. It is beneficial to customers as well as drivers. I hope to see this industry flourish.
Saturday, 16 August 2014
Finding the file or device pointed to by a file descriptor
I had been noticing that Firefox starts off with around 400mb and reaches around 1.4 gb as I keep using it throughout the day. Also, CPU utilization clocked at 25% on my i7. So, I thought of trying to mess around in the hope of finding something interesting. I found the pid using the following.
ps aux | grep firefox
I ran an
strace to try and see what was keeping it so busy.strace -p <pid_of_firefox_process>
This is what I got.
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 4294967295) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 4294967295) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 4294967295) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
getrusage(RUSAGE_SELF, {ru_utime={17387, 398261}, ru_stime={821, 999917}, ...}) = 0
getrusage(RUSAGE_SELF, {ru_utime={17387, 438261}, ru_stime={821, 999917}, ...}) = 0
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
write(18, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 4294967295) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 4294967295) = 1 ([{fd=17, revents=POLLIN}])
read(17, "\372", 1) = 1
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 0) = 0 (Timeout)
recvmsg(4, 0x7fff427b9fb0, 0) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=5, events=POLLIN}, {fd=4, events=POLLIN}, {fd=17, events=POLLIN}, {fd=19, events=POLLIN}], 4, 4294967295) = 1 ([{fd=17, revents=POLLIN}])
Now, I wanted to know the files pointed to by file descriptors 4, 5, 17, 19. To look those use, I read that I can use
/proc filesystem. So, I just tried simply looking it up there.ls -l /proc/<pid_of_firefox_process>/fd
The files turned out to be as follows:
- 4 - a socket
- 5 - anon_inode:[eventfd]
- 17 - a pipe
- 19 - another socket
Subscribe to:
Posts (Atom)









