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Tweak post formatting

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Xevion
2023-09-19 12:05:47 -05:00
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_posts/2023-07-26-race-conditions-in-signal-handlers.md
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@@ -113,7 +113,7 @@ there's a way to check whether signal handlers have been provided or a process.
On Unix systems (which is the only place you're going to find Unix signals), there's a special pseudo-filesystem that
provides intimate details on a process. This includes things like the process's name, state, PID, memory usage, threads,
and of course: signal handlers.
and of course: *signal handlers*.
See below, the contents of `/proc/<pid>/status` for a process:
@@ -151,7 +151,7 @@ See below, the contents of `/proc/<pid>/status` for a process:
43 │ CapPrm: 0000000000000000
```
We're interested in SigCgt, which is a bitmask of signals that are caught by the process. The specific bit depends on the platform, but in Python, this can be found in the signal module:
We're interested in `SigCgt` (line 41), which is a bitmask of signals that are caught by the process. The specific bit depends on the platform, but in Python, this can be found in the signal module:
```python
>>> from signal import SIGUSR1
@@ -159,7 +159,7 @@ We're interested in SigCgt, which is a bitmask of signals that are caught by the
10
```
We can parse the SigCgt value using the the `int` function and setting the radix to 16 (hexadecimal).
We can parse the `SigCgt` value using the the `int` function and setting the radix to 16 (hexadecimal).
```python
>>> int("0000000f40800ef8", 16)
@@ -177,7 +177,7 @@ Checking whether or not the Nth bit is set can be done with the bitwise AND oper
If the result is non-zero, the bit is set. If the result is zero, the bit is not set.
By simply polling the process's signal handlers, we can wait for the signal handler to be registered before sending the SIGUSR1 signal.
By simply polling the process's signal handlers, we can wait for the signal handler to be registered before sending the `SIGUSR1` signal.
Signal handlers are typically registered quickly, and they're