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Full Discussion: Help with trap and signals
Top Forums Shell Programming and Scripting Help with trap and signals Post 302843654 by jim mcnamara on Wednesday 14th of August 2013 10:13:14 AM
Old 08-14-2013
sleep invokes a wait like
Code:
nanosleep()

and sets a signal handler for SIGALRM.

But.
Code:
/usr/bin/sleep

is run in a separate child process. So, ctrl/c is sent to the child process not the parent.

It is analagous to running the
Code:
ls

command on a huge directory. ctrl/c stops the child
Code:
/usr/bin/ls

executable image before it dumps 10 zillion files to the screen, not the the parent process.


Lose the sleep command. It looks to me like you are trying out bash coding. ctrl/c only "works" on the parent when the parent is running an actual bash command like some kind of loop. Otherwise repeated ctrl/c keystrokes are required, so that the signal get delivered during the execution of a susceptible piece of code.

Last edited by jim mcnamara; 08-14-2013 at 11:24 AM..
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IRSEND(1)							   User Commands							 IRSEND(1)

NAME
irsend - basic LIRC program to send infra-red commands SYNOPSIS
irsend [options] DIRECTIVE REMOTE CODE [CODE...] DESCRIPTION
Asks the lircd daemon to send one or more CIR (Consumer Infra-Red) commands. This is intended for remote control of electronic devices such as TV boxes, HiFi sets, etc. DIRECTIVE can be: SEND_ONCE - send CODE [CODE ...] once SEND_START - start repeating CODE SEND_STOP - stop repeating CODE LIST - list configured remote items SET_TRANSMITTERS - set transmitters NUM [NUM ...] SIMULATE - simulate IR event REMOTE is the name of a remote, as described in the lircd configuration file. CODE is the name of a remote control key of REMOTE, as it appears in the lircd configuration file. NUM is the transmitter number of the hardware device. For the LIST DIRECTIVE, REMOTE and/or CODE can be empty: LIST "" "" - list all configured remote names LIST REMOTE "" - list all codes of REMOTE LIST REMOTE CODE - list only CODE of REMOTE The SIMULATE command only works if it has been explicitly enabled in lircd. -h --help display usage summary -v --version display version -d --device use given lircd socket [/var/run/lirc/lircd] -a --address=host[:port] connect to lircd at this address -# --count=n send command n times EXAMPLES
irsend LIST DenonTuner "" irsend SEND_ONCE DenonTuner PROG-SCAN irsend SEND_ONCE OnkyoAmpli VOL-UP VOL-UP VOL-UP VOL-UP irsend SEND_START OnkyoAmpli VOL-DOWN ; sleep 3 irsend SEND_STOP OnkyoAmpli VOL-DOWN irsend SET_TRANSMITTERS 1 irsend SET_TRANSMITTERS 1 3 4 irsend SIMULATE "0000000000000476 00 OK TECHNISAT_ST3004S" FILES
/etc/lirc/lircd.conf Default lircd configuration file. It should contain all the remotes, their infra-red codes and the corresponding timing and wave- form details. DIAGNOSTICS
If lircd is not running (or /var/run/lirc/lircd lacks write permissions) irsend aborts with the following diagnostics: "irsend: could not connect to socket" "irsend: Connection refused" (or "Permission denied"). SEE ALSO
The documentation for lirc is maintained as html pages. They are located under html/ in the documentation directory. lircd(8), mode2(1), smode2(1), xmode2(1), irrecord(1), irw(1), http://www.lirc.org. irsend 0.9.0-pre1 October 2010 IRSEND(1)
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