stat

Overview

The stat command displays detailed information about files and filesystems, including permissions, timestamps, size, and inode details.

Syntax

stat [options] file...

Common Options

Option Description
-c format Custom format
-f Display filesystem status
-L Follow symbolic links
-t Terse format
--printf=format Printf-style format

File Information Fields

Field Description
File Filename
Size File size in bytes
Blocks Number of blocks allocated
IO Block Filesystem block size
Device Device ID
Inode Inode number
Links Number of hard links
Access File permissions
Uid/Gid User and group IDs
Access time Last access time
Modify time Last modification time
Change time Last status change time
Birth time File creation time (if supported)

Key Use Cases

  1. View detailed file information
  2. Check file permissions and ownership
  3. Analyze timestamps
  4. Filesystem analysis
  5. Debugging file issues

Examples with Explanations

Example 1: Basic File Information

stat file.txt

Shows complete file information

Example 2: Filesystem Information

stat -f /home

Displays filesystem statistics

Example 3: Custom Format

stat -c "%n %s %y" file.txt

Shows filename, size, and modification time

Format Specifiers

Specifier Description
%n Filename
%s Total size in bytes
%b Number of blocks
%f Raw mode in hex
%F File type
%a Access rights in octal
%A Access rights in human readable form
%u User ID
%g Group ID
%U User name
%G Group name
%x Time of last access
%y Time of last modification
%z Time of last change

Common Usage Patterns

  1. Check permissions:

    stat -c "%a %n" file.txt

  2. Compare timestamps:

    stat -c "%y %n" file1 file2

  3. Find inode number:

    stat -c "%i" file.txt

Timestamp Analysis

Understanding timestamps: - Access time (atime): Last read - Modify time (mtime): Last content change - Change time (ctime): Last metadata change - Birth time (btime): Creation time (ext4, btrfs)

Performance Analysis

  • Fast operation
  • No file content reading
  • Minimal system resources
  • Good for scripting
  • Efficient metadata access

Additional Resources

Best Practices

  1. Use custom formats for scripting
  2. Check filesystem support for features
  3. Understand timestamp meanings
  4. Use with other tools for analysis
  5. Consider timezone effects

Scripting Examples

  1. Find files modified today:

    stat -c "%y %n" * | grep $(date +%Y-%m-%d)

  2. Check if file is executable:

    [[ $(stat -c "%a" file) -ge 100 ]] && echo "Executable"

  3. Compare file ages:

    stat -c "%Y" file1 file2 | sort -n

Filesystem Information

Using -f option shows: - Filesystem type - Block size - Total blocks - Free blocks - Available blocks - Total inodes - Free inodes

Troubleshooting

  1. Permission denied errors
  2. Symbolic link handling
  3. Filesystem compatibility
  4. Timestamp interpretation
  5. Format string errors

Integration Examples

  1. With find:

    find . -name "*.txt" -exec stat -c "%n %s" {} \;

  2. With awk:

    stat -c "%s %n" * | awk '$1 > 1000000'

  3. Monitoring script:

    stat -c "%y" important.txt > timestamp.log