Render text as a PBM image. See also:
pbmtextps
. More information: https://netpbm.sourceforge.net/doc/pbmtext.html.
pbmtext "Hello World!" > path/to/output.pbm
echo "Hello\nWorld!" | pbmtext > path/to/output.pbm
pbmtext -font path/to/font.pbm "Hello World!" > path/to/output.pbm
echo "Hello\nWorld!" | pbmtext -space 3 -lspace 10 > path/to/output.pbm