[SOLVED] customizing the statusbar dwmblock (DWM - Tiling Window Manager)

apoorv569 · 06-11-2020, 10:58 AM

Quote:

Originally Posted by shruggy

Put a space bethween " and ]]. I'd probably just test for presence of the string:

Code:

if dmesg -S|grep -q "USB Mass Storage device detected"; then

yes i wanted to this check for the presence of the string too, but didn't know how to do it. so you check for a string -q flag?

apoorv569 · 06-11-2020, 11:10 AM

Quote:

Originally Posted by TB0ne

No worries...as long as you're learning, you'll keep getting better. You're missing a space after the detected" and before the ]]. That should get rid of that message. And after thinking about it for a bit, try this instead:

Code:

if [[ "$(dmesg -S | tail | grep "usb-storage")" =~ "USB Mass Storage device detected" ]]; then
           icon=" ��️ "
           else
           icon=""
   fi
   
   printf "%s%s\\n" "$icon"

...which will check for the presence of the string in what you get. That way, you can modify this to do different things if you plug in a mouse or some other USB device.

yes this is working. but the script that i sent after adding the space it didn't give any error but also wont show anything when usb connected. so i copied yours. can you tell me what the ~ after = means.

shruggy · 06-11-2020, 11:13 AM

From the Bash Reference Manual:

Quote:

An additional binary operator, =~, is available, with the same precedence as == and !=. When it is used, the string to the right of the operator is considered a POSIX extended regular expression and matched accordingly (as in regex(3)).

apoorv569 · 06-11-2020, 11:18 AM

Quote:

Originally Posted by TB0ne

So that's the device you need to query with fuser.../dev/snd/pcmC1D0c, and incorporate that into your script.

ok so for microphone i did this

Code:

   #!/bin/bash
   
        if [[ "$(fuser /dev/snd/pcmC1D0c)" != "" ]]; then
          icon="  "
        else
          icon=""
        fi
   
   printf "%s%s\\n" "$icon"

its working it doesn't show anything when mic not is use but when in use it shows icon but its also giving me this output when i run the script in terminal

Code:

/dev/snd/pcmC1D0c:  m
 

apoorv569 · 06-11-2020, 11:24 AM

Quote:

Originally Posted by shruggy

From the Bash Reference Manual:

thank you i bookmarked the page for future reference. i guess i can `man bash` also.?

shruggy · 06-11-2020, 11:27 AM

fuser prints the name of device to stderr. So, add 2>/dev/null

Code:

if [[ -n "$(fuser /dev/snd/pmcC1D0c 2>/dev/null)" ]]; then

Quote:

Originally Posted by apoorv569

i guess i can `man bash` also.?

Yes, it contains the same text.

apoorv569 · 06-11-2020, 11:39 AM

Quote:

Originally Posted by shruggy

fuser prints the name of device to stderr. So, add 2>/dev/null

Code:

if [[ -n "$(fuser /dev/snd/pmcC1D0c 2>/dev/null)" ]]; then

Yes, it contains the same text.

what is the -n for that you added in the beginning. and what does 2> mean? i guess /dev/null is like show nothing?
if you can point me to a man page or reference guide for this .

apoorv569 · 06-11-2020, 12:06 PM

Quote:

Originally Posted by TB0ne

No worries...as long as you're learning, you'll keep getting better. You're missing a space after the detected" and before the ]]. That should get rid of that message. And after thinking about it for a bit, try this instead:

Code:

if [[ "$(dmesg -S | tail | grep "usb-storage")" =~ "USB Mass Storage device detected" ]]; then
           icon=" ��️ "
           else
           icon=""
   fi
   
   printf "%s%s\\n" "$icon"

...which will check for the presence of the string in what you get. That way, you can modify this to do different things if you plug in a mouse or some other USB device.

all scripts are working now. but this usb script, when i plug a usb drive it shows icon as expected, but if plug another usb in different port,at the same time so i have now 2 usb's, the icon disappears.

shruggy · 06-11-2020, 12:12 PM

Quote:

Originally Posted by apoorv569

what is the -n for that you added in the beginning.

See Bash Conditional Expressions. If you omit -n it has the same effect: true if string is not empty.

Quote:

Originally Posted by apoorv569

and what does 2> mean? i guess /dev/null is like show nothing?

See this answer as well as File Redirection in BashGuide and I/O Redirection in Advanced Bash-Scripting Guide.

2 is the file descriptor (FD) for standard error stream (stderr).

apoorv569 · 06-11-2020, 12:21 PM

Quote:

Originally Posted by shruggy

See Bash Conditional Expressions. If you omit -n it has the same effect: true if string is not empty.

See File Redirection in BashGuide as well as I/O Redirection in Advanced Bash-Scripting Guide.

2 is the file descriptor (FD) for standard error stream (stderr).

thank you.i have bookmarked all the pages.

apoorv569 · 06-11-2020, 11:33 PM

Quote:

Originally Posted by TB0ne

No worries...as long as you're learning, you'll keep getting better. You're missing a space after the detected" and before the ]]. That should get rid of that message. And after thinking about it for a bit, try this instead:

Code:

if [[ "$(dmesg -S | tail | grep "usb-storage")" =~ "USB Mass Storage device detected" ]]; then
           icon=" ��️ "
           else
           icon=""
   fi
   
   printf "%s%s\\n" "$icon"

...which will check for the presence of the string in what you get. That way, you can modify this to do different things if you plug in a mouse or some other USB device.

this script is not good enough. when i connect 1 usb it gives this

Code:

[  151.134547] usb-storage 1-2:1.0: USB Mass Storage device detected
[  151.138129] scsi host2: usb-storage 1-2:1.0
[  152.157810] scsi 2:0:0:0: Direct-Access     MBIL SSM Moser Baer Disk  8.07 PQ: 0 ANSI: 4
[  152.158051] sd 2:0:0:0: Attached scsi generic sg2 type 0
[  152.158711] sd 2:0:0:0: [sdb] 31027200 512-byte logical blocks: (15.9 GB/14.8 GiB)
[  152.159381] sd 2:0:0:0: [sdb] Write Protect is off
[  152.159387] sd 2:0:0:0: [sdb] Mode Sense: 23 00 00 00
[  152.160066] sd 2:0:0:0: [sdb] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[  152.924036]  sdb: sdb1 sdb2 sdb3
[  152.926370] sd 2:0:0:0: [sdb] Attached SCSI removable disk

when i connect another usb at the same time it gives this

Code:

[  364.948449] scsi host3: usb-storage 1-1:1.0
[  366.206529] scsi 3:0:0:0: Direct-Access     SRT      USB              1100 PQ: 0 ANSI: 4
[  366.206834] sd 3:0:0:0: Attached scsi generic sg3 type 0
[  366.207126] sd 3:0:0:0: [sdc] 15818752 512-byte logical blocks: (8.10 GB/7.54 GiB)
[  366.207629] sd 3:0:0:0: [sdc] Write Protect is off
[  366.207631] sd 3:0:0:0: [sdc] Mode Sense: 43 00 00 00
[  366.208117] sd 3:0:0:0: [sdc] No Caching mode page found
[  366.208119] sd 3:0:0:0: [sdc] Assuming drive cache: write through
[  366.237610]  sdc: sdc1
[  366.239332] sd 3:0:0:0: [sdc] Attached SCSI removable disk

which doesn't have usb-storage to grep so the icon disappears even though i have 2 usb connected.

when i connect a usb portable 2.5" hdd it gives this ( i extended tail range to -n 15 )

Code:

[  659.426376] usb 1-3: Product: USB 3.0 Device
[  659.426377] usb 1-3: Manufacturer: USB 3.0 Device
[  659.426379] usb 1-3: SerialNumber: 00000000B032
[  659.433060] scsi host4: uas
[  659.433839] scsi 4:0:0:0: Direct-Access     WDC WD10 SPZX-00Z10T0     0117 PQ: 0 ANSI: 6
[  659.435213] sd 4:0:0:0: Attached scsi generic sg4 type 0
[  659.435840] sd 4:0:0:0: [sdd] 1953525168 512-byte logical blocks: (1.00 TB/932 GiB)
[  659.435842] sd 4:0:0:0: [sdd] 4096-byte physical blocks
[  659.436038] sd 4:0:0:0: [sdd] Write Protect is off
[  659.436041] sd 4:0:0:0: [sdd] Mode Sense: 53 00 10 08
[  659.436349] sd 4:0:0:0: [sdd] Disabling FUA
[  659.436351] sd 4:0:0:0: [sdd] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[  659.436476] sd 4:0:0:0: [sdd] Optimal transfer size 33553920 bytes not a multiple of physical block size (4096 bytes)
[  659.578561]  sdd: sdd1
[  659.580012] sd 4:0:0:0: [sdd] Attached SCSI disk

usb hdd doesn't even have a usb-storage to grep.

also when 1 of the flash drive was connected and i rebooted the icon didn't show because the dmesg tail was about my wifi being connected and networkmanager.

any idea's for improving this script, as this is not reliable.

apoorv569 · 06-12-2020, 04:29 AM

i serched the internet a little and found that i could use udev for detecting usb. but im not sure how to use use udev to get the info i need. but i did find this command

Code:

udevadm monitor --kernel --property --subsystem-match=usb

so i tried making the script like this

Code:

   #!/bin/bash
  
   if [[ "$(udevadm monitor --kernel --property --subsystem-match=usb | head -n 4 | tail -n 1 | awk '{print $2}')" == "add" ]]; then
           icon="  "
   #elif [[ "$(udevadm monitor --kernel --property --subsystem-match=usb | head -n 4 | tail -n 1 | awk '{print $2}')" =~ "unbind" ]]; then
           icon=""
   fi
  
   printf "%s%s\\n" "$icon"

however when i run the script it waits for me to plug usb to show, and when i added it in my block list dwmblock did not show at all i had to remove it. i dont know how to use udev to extract the data.

shruggy · 06-12-2020, 06:17 AM

Well, udevadm monitor will just sit there and wait for events until you kill it. It will never transfer control to your script, so the script will be stuck reading the output from udevadm monitor forever.

Besides, you're only interested in storage devices, right? So you don't want the script to fire each time you plug in a new USB mouse or some such.

I'd rather evaluate the output of udisksctl dump like I did in that thread. This should be enough:

Code:

udisksctl dump|grep 'HintAuto:\s*true'

apoorv569 · 06-12-2020, 06:51 AM

Quote:

Originally Posted by shruggy

Well, udevadm monitor will just sit there and wait for events until you kill it. It will never transfer control to your script, so the script will be stuck reading the output from udevadm monitor forever.

Besides, you're only interested in storage devices, right? So you don't want the script to fire each time you plug in a new USB mouse or some such.

I'd rather evaluate the output of udisksctl dump like I did in that thread. This should be enough:

Code:

udisksctl dump|grep 'HintAuto:\s*true'

for now i just want it for storage device.

this command

Code:

udisksctl dump|grep 'HintAuto:\s*true'

gives me

Code:

    HintAuto:                   true

even when there is no usb is connected.

but the link you sent me for ubuntu forums i think i can use this

Code:

udisksctl dump|awk -F':\n' -v'RS=\n\n' '/[ \t]*HintAuto:[ \t]*true/&&/\.Filesystem:/{sub(/.*\/UDisks2\//,"",$1); print $1}'

as this doesn't gives any output when no usb is connected, and shows (using all 3 usb ports)

Code:

block_devices/sdb1
block_devices/sdc1
block_devices/sdd1
block_devices/sdd2
block_devices/sdd3

maybe something like this

Code:

if [[ "$(udisksctl dump|awk -F':\n' -v'RS=\n\n' '/[ \t]*HintAuto:[ \t]*true/&&/\.Filesystem:/{sub(/.*\/UDisks2\//,"",$1); print $1}')" != " " ]]; then
           icon="  "
   else
           icon=""
   fi
  
   printf "%s%s\\n" "$icon"

shruggy · 06-12-2020, 07:42 AM

Ah, I don't have a DVD drive or card reader, so didn't think about other kinds of devices beyond USB that may have HintAuto set to true.

Well, the awk script enumerates partitions on all removable storage devices. I believe in your case it could be a bit simplified. How about

Code:

udisksctl dump|awk -F':\n' -vRS= '/[ \t]*HintAuto:[ \t]*true/&&/\.Filesystem:/{print "found"}'