C

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Why this exists Scanning logs is the everyday job of small C tools: it is what grep and wc do. The details that make a tool reliable are the ones beginners skip: checking that the file opened, coping with a line longer…

Scanning a Log File: fopen, fgets, sscanf and Error Handling

Read a log file line by line with fgets, handle over-long lines correctly, count levels with strstr, parse structured fields with sscanf using width limits, and report I/O errors with perror and the right exit code.

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