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Passing the file name as a command-line argument - نسخة قابلة للطباعة

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Passing the file name as a command-line argument - ftth - 11-04-2025

How to run the script:
bash
كود:
./your_script.sh /path/to/input_file.txt
[b]Inside [/b]
كود:
your_script.sh
[b]:[/b]
You would use the variable 
كود:
$1
 to refer to the file path. 
bash
كود:
#!/bin/bash

INPUT_FILE="$1"

# Check if file was provided and exists
if [ -z "$INPUT_FILE" ]; then
  echo "Usage: $0 <input_file>"
  exit 1
fi

if [ ! -f "$INPUT_FILE" ]; then
  echo "Error: File not found at $INPUT_FILE"
  exit 1
fi

# Example: Read the file line by line
while IFS= read -r line; do
  echo "Next line: $line"
done < "$INPUT_FILE"
Redirecting the file content to standard input
The script reads directly from its standard input (stdin), which the shell connects to the file's content using the 
كود:
<
 operator. 
[b]How to run the script:[/b]
bash
كود:
./your_script.sh < /path/to/input_file.txt
[b]Inside [/b]
كود:
your_script.sh
[b]:[/b]
The script uses commands that read from stdin, such as 
كود:
read
, 
كود:
cat
, 
كود:
grep
, 
كود:
tr
, etc. 
bash
كود:
#!/bin/bash

# Example: Read from standard input line by line
while IFS= read -r line; do
  echo "Next line: $line"
done
# The loop reads from stdin because no redirection is specified in the while command itself.

# Alternatively, other commands can use stdin directly:
# tr 'a-z' 'A-Z' # This would convert all input to uppercase
3. Using custom argument parsing (for 
كود:
input_file=
)
If you want to use the specific 
كود:
input_file=
 format as in your example, you need to parse the arguments manually within your script.
[b]How to run the script:[/b]
bash
كود:
./your_script.sh input_file=/path/to/file.txt
[b]Inside [/b]
كود:
your_script.sh
[b]:[/b]
bash
كود:
#!/bin/bash

for arg in "$@"; do
  case "$arg" in
    input_file=*)
      INPUT_FILE="${arg#*=}" # Extract the value after the '='
      ;;
    *)
      # Handle other arguments or errors
      ;;
  esac
done

# Now you can use $INPUT_FILE as in Method 1
if [ -f "$INPUT_FILE" ]; then
  echo "Processing file: $INPUT_FILE"
  # ... processing code here ...
else
  echo "Error: File not found or not specified."
fi