WebMar 9, 2014 · void openFile ( const string & pathToFile, gzFile & fileStream, const char * mode) { fileStream = gzopen (pathToFile.c_str (), mode); if (fileStream == NULL) { cerr & split ( char * buf, const char * delim, vector & tokens) { tokens.clear (); char * pch; pch = strtok (buf, delim); while (pch != NULL) { tokens.push_back (string (pch)); pch = … WebSorted by: 18. For decompression: char buf [1024*1024*16]; gzFile *fi = (gzFile *)gzopen ("file.gz","rb"); gzrewind (fi); while (!gzeof (fi)) { int len = gzread (fi,buf,sizeof (buf)); //buf …
How to read a .gz file line-by-line in C++? - Stack Overflow
WebJun 29, 2024 · For my example file (~35m reads of ~75bp) this took: real 0m49.670s user 0m49.364s sys 0m0.304s Compared with your example: real 0m43.616s user 1m35.060s sys 0m5.240s Konrad's solution (in my hands): real 0m39.682s user 1m11.900s sys 0m5.112s (By the way, just zcat-ing the data file to /dev/null): WebJun 23, 2015 · I found an example online which is very useful, which works for me: blog: Compression of Simulation Data using ZLib Bascially, using gzwrite and gzread for writing and reading just like writing regular files. When writing, first write the string size, then write the string. Same order for reading. ukc world hunt 2022
zlib Usage Example
WebI guess you are using zlib-1.2.3. In this version, gzgets () is virtually calling gzread () for each byte. Calling gzread () in this way has a big overhead. You can compare the CPU time of calling gzread (gzfp, buffer, 4096) once and of calling gzread (gzfp, buffer, 1) for 4096 times. The result is the same, but the CPU time is hugely different. WebThe gzread() function shall read data from the compressed file referenced by file, which shall have been opened in a read mode (see gzopen() and gzdopen()). The gzread() … WebMar 9, 2014 · 1 Answer. Sorted by: 0. strtok () operates on a null-terminated string. You are providing a buffer read from, presumably, a text file. There is no null. So strtok () is … thomas t320 specs