## Why Does My Go C-Shared Library Hang on Network Calls in a Forked Child Process?-Golang-php.cn

Home

Backend Development

Golang

## Why Does My Go C-Shared Library Hang on Network Calls in a Forked Child Process?

Susan Sarandon

Oct 30, 2024 am 11:06 AM

## Why Does My Go C-Shared Library Hang on Network Calls in a Forked Child Process?

Debugging Go C-shared Library Problems: Hangs on Network Calls

Issue

A Go program encounters a hang when calling http.Post() while built as a C shared library (-buildmode=c-shared). However, the standard executable binary (GOOS=linux GOARCH=amd64 ./example) returns the correct value.

Source of the Problem

The issue arises because the Go runtime is loaded when the C shared library is loaded by the parent process. However, when the library is used in a forked child process, the Go runtime is not loaded correctly, leading to unpredictable behavior and hanging calls.

Debugging Steps

Inspect system calls with strace: The strace tool can reveal system calls being made by the process. For example, running strace -fp PID may show calls to futex and Post operations, such as futex(0x7f618b2c1cd0, FUTEX_WAKE, 1) and Post().
Add profiling to the HTTP server: To gather information about the state of the program when it hangs, add profiling to the HTTP server using http.ListenAndServe("localhost:6060", nil). This will run a profiler on port 6060, which can be inspected to identify the cause of the hang.

Solution

The solution involves controlling the loading of the Go runtime within the child process. To do this:

Use dlopen to load the Go shared library after the child process is forked.
Use dlsym to access symbols from the Go library within the child process.

By loading the Go runtime explicitly in the child process, it is ensured that the runtime is initialized correctly and network calls can be made successfully.

The above is the detailed content of ## Why Does My Go C-Shared Library Hang on Network Calls in a Forked Child Process?. For more information, please follow other related articles on the PHP Chinese website!

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Learn Go String Manipulation: Working with the 'strings' PackageMay 09, 2025 am 12:07 AM

Go's "strings" package provides rich features to make string operation efficient and simple. 1) Use strings.Contains() to check substrings. 2) strings.Split() can be used to parse data, but it should be used with caution to avoid performance problems. 3) strings.Join() is suitable for formatting strings, but for small datasets, looping = is more efficient. 4) For large strings, it is more efficient to build strings using strings.Builder.

Go: String Manipulation with the Standard 'strings' PackageMay 09, 2025 am 12:07 AM

Go uses the "strings" package for string operations. 1) Use strings.Join function to splice strings. 2) Use the strings.Contains function to find substrings. 3) Use the strings.Replace function to replace strings. These functions are efficient and easy to use and are suitable for various string processing tasks.

Mastering Byte Slice Manipulation with Go's 'bytes' Package: A Practical GuideMay 09, 2025 am 12:02 AM

ThebytespackageinGoisessentialforefficientbyteslicemanipulation,offeringfunctionslikeContains,Index,andReplaceforsearchingandmodifyingbinarydata.Itenhancesperformanceandcodereadability,makingitavitaltoolforhandlingbinarydata,networkprotocols,andfileI

Learn Go Binary Encoding/Decoding: Working with the 'encoding/binary' PackageMay 08, 2025 am 12:13 AM

Go uses the "encoding/binary" package for binary encoding and decoding. 1) This package provides binary.Write and binary.Read functions for writing and reading data. 2) Pay attention to choosing the correct endian (such as BigEndian or LittleEndian). 3) Data alignment and error handling are also key to ensure the correctness and performance of the data.

Go: Byte Slice Manipulation with the Standard 'bytes' PackageMay 08, 2025 am 12:09 AM

The"bytes"packageinGooffersefficientfunctionsformanipulatingbyteslices.1)Usebytes.Joinforconcatenatingslices,2)bytes.Bufferforincrementalwriting,3)bytes.Indexorbytes.IndexByteforsearching,4)bytes.Readerforreadinginchunks,and5)bytes.SplitNor

Go encoding/binary package: Optimizing performance for binary operationsMay 08, 2025 am 12:06 AM

Theencoding/binarypackageinGoiseffectiveforoptimizingbinaryoperationsduetoitssupportforendiannessandefficientdatahandling.Toenhanceperformance:1)Usebinary.NativeEndianfornativeendiannesstoavoidbyteswapping.2)BatchReadandWriteoperationstoreduceI/Oover

Go bytes package: short reference and tipsMay 08, 2025 am 12:05 AM

Go's bytes package is mainly used to efficiently process byte slices. 1) Using bytes.Buffer can efficiently perform string splicing to avoid unnecessary memory allocation. 2) The bytes.Equal function is used to quickly compare byte slices. 3) The bytes.Index, bytes.Split and bytes.ReplaceAll functions can be used to search and manipulate byte slices, but performance issues need to be paid attention to.

Go bytes package: practical examples for byte slice manipulationMay 08, 2025 am 12:01 AM

The byte package provides a variety of functions to efficiently process byte slices. 1) Use bytes.Contains to check the byte sequence. 2) Use bytes.Split to split byte slices. 3) Replace the byte sequence bytes.Replace. 4) Use bytes.Join to connect multiple byte slices. 5) Use bytes.Buffer to build data. 6) Combined bytes.Map for error processing and data verification.

See all articles