libpbm(3)                        UNIX System V                        libpbm(3)


NAME
      libpbm - functions to support portable bitmap programs

SYNOPSIS
      #include <pbm.h>
      cc ... libpbm.a


DESCRIPTION - PACKAGE-WIDE ROUTINES
   KEYWORD MATCHING
      int pm_keymatch( char* str, char* keyword, int minchars )

      Does a case-insensitive match of str against keyword.  str can be a
      leading sunstring of keyword, but at least minchars must be present.

   LOG BASE TWO
      int pm_maxvaltobits( int maxval )
      int pm_bitstomaxval( int bits )

      Convert between a maxval and the minimum number of bits required to hold
      it.

   MESSAGES AND ERRORS
      void pm_message( char* fmt, ... )

      printf() style routine to write an informational message.

      void pm_error( char* fmt, ... )

      printf() style routine to write an error message and abort.

      void pmusage( char* usage )

      Write a usage message.  The string should indicate what arguments are to
      be provided to the program.

   GENERIC FILE MANAGEMENT
      FILE* pm_openr( char* name )

      Open the given file for reading, with appropriate error checking.  A
      filename of "-" is taken as equivalent to stdin.

      FILE* pmopenw( char* name )

      Open the given file for writing, with appropriate error checking.

      void pm_close( FILE* fp )

      Close the file descriptor, with appropriate error checking.





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libpbm(3)                        UNIX System V                        libpbm(3)


   ENDIAN I/O
      int pm_readbigshort( FILE* in, short* sP )
      int pm_writebigshort( FILE* out, short s )
      int pm_readbiglong( FILE* in, long* lP )
      int pm_writebiglong( FILE* out, long l )
      int pm_readlittleshort( FILE* in, short* sP )
      int pm_writelittleshort( FILE* out, short s )
      int pm_readlittlelong( FILE* in, long* lP )
      int pm_writelittlelong( FILE* out, long l )

      Routines to read and write short and long ints in either big- or little-
      endian byte order.

DESCRIPTION - PBM-SPECIFIC ROUTINES
   TYPES AND CONSTANTS
      typedef ... bit;
      #define PBM_WHITE ...
      #define PBM_BLACK ...

      each bit should contain only the values of PBMWHITE or PBMBLACK.

      #define PBM_FORMAT ...
      #define RPBM_FORMAT ...
      #define PBM_TYPE PBM_FORMAT
      #define PBM_FORMAT_TYPE(f) ...

      For distinguishing different file formats and types.

   INITIALIZATION
      void pbm_init( int* argcP, char* argv[] )

      All PBM programs must call this routine.

   MEMORY MANAGEMENT
      bit** pbm_allocarray( int cols, int rows )

      Allocate an array of bits.

      bit* pbm_allocrow( int cols )

      Allocate a row of the given number of bits.

      void pbm_freearray( bit** bits, int rows )

      Free the array allocated with pbmallocarray() containing the given
      number of rows.

      void pbm_freerow( bit* bitrow )

      Free a row of bits.




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libpbm(3)                        UNIX System V                        libpbm(3)


   READING FILES
      void pbm_readpbminit( FILE* fp, int* colsP, int* rowsP, int* formatP )

      Read the header from a PBM file, filling in the rows, cols and format
      variables.

      void pbmreadpbmrow( FILE* fp, bit* bitrow, int cols, int format )

      Read a row of bits into the bitrow array.  Format and cols were filled in
      by pbmreadpbminit().

      bit** pbm_readpbm( FILE* fp, int* colsP, int* rowsP )

      Read an entire bitmap file into memory, returning the allocated array and
      filling in the rows and cols variables.  This function combines
      pbmreadpbminit(), pbmallocarray() and pbmreadpbmrow().

   WRITING FILES
      void pbm_writepbminit( FILE* fp, int cols, int rows, int forceplain )

      Write the header for a portable bitmap file.  The forceplain flag forces
      a plain-format file to be written, as opposed to a raw-format one.

      void pbm_writepbmrow( FILE* fp, bit* bitrow, int cols, int forceplain )

      Write a row from a portable bitmap.

      void pbm_writepbm( FILE* fp, bit** bits, int cols, int rows, int forceplain )

      Write the header and all data for a portable bitmap.  This function
      combines pbmwritepbminit() and pbmwritepbmrow().

SEE ALSO
      libpgm(3), libppm(3), libpnm(3)

AUTHOR
      Copyright (C) 1989, 1991 by Tony Hansen and Jef Poskanzer.

















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