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Re: Segfault using `watch -c` with ANSI escapes in output

On 18/04/2017 16:10, Brian Inglis wrote:
On 2017-04-18 06:36, Adam Dinwoodie wrote:
I'm seeing a segfault from using `watch -c` with commands that output
ANSI colour sequences, which is a bit sad given the whole point of the
`-c` is to get the ANSI colour sequences to be displayed.
Simple test case:
    $ echo -e '\e[0;32mGreen\e[0;0m' >escapes
    $ cat escapes  # Text is green in my terminal
    $ xxd escapes
    00000000: 1b5b 303b 3332 6d47 7265 656e 1b5b 303b  .[0;32mGreen.[0;
    00000010: 306d 0a                                  0m.
    $ watch -c cat escapes
    Segmentation fault (core dumped)

Dies on me too:
$ uname -srvmo
CYGWIN_NT-10.0 2.8.0(0.309/5/3) 2017-04-01 20:47 x86_64 Cygwin
$ watch --version
watch from procps-ng 3.3.11

gdb crashes with dumper .core.

$ gdb watch
Reading symbols from watch...(no debugging symbols found)...done.

If you install procps-ng-debuginfo for symbols...

(gdb) run -c cat e
Starting program: /usr/bin/watch -c cat e
[New Thread 436.0x19dc]
[New Thread 436.0x1e44]
[New Thread 436.0x834]
[New Thread 436.0x12d0]
[New Thread 436.0x1508]
[New Thread 436.0xa24]

Program received signal SIGSEGV, Segmentation fault.
0x00000001004029b0 in ?? ()
(gdb) bt
#0  0x00000001004029b0 in ?? ()

... you'll see the obvious mistake which has been fixed upstream for a while [1].

[1] https://gitlab.com/procps-ng/procps/issues/11

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